By on June 2, 2012

Not wanting to let the proverbial grass grow under my feet, I figured now was as good a time as any to proceed with the “rant” threatened of while in the midst of my “Of Honda’s and Miracles” piece. While I was contemplating said rant, it also seemed like a good time to make a quasi-collection of additional rage against other automotive technologies that, over the years, I’ve found to be considerably more than a useless nuisance.

In the interests of clarity and brevity, I limited the scope to designs currently being used by virtually ALL auto manufacturers. I may, in the future, if overcome by intense feelings of either abstract nostalgia or acute vindictiveness, single out certain “rogue” designs from the past and present. I will leave all of the Why’s and Wherefores to Conspiracy Theorists. Now…TO THE BIN!

The Drum Brake
Ever since my High School Auto Shop days, I’ve tried to resolve my intense dislikes for all things Drum.

Yes, of course I learned to use the tools effectively, really mastering my service technique; and I believe I have been able to get the most of whatever this design has to offer on any vehicle passing through my repair bay. I even went so far as to drive my restored 1967 Ram-Air Stick Shifted Pontiac Firebird 400 on the freeways of Los Angeles, and, on top of that, on a couple of spirited excursions up U.S. Highway 1 to the Monterey Historic car weekend—with these spiteful mechanisms attached to ALL FOUR wheels, no less!

The act of stopping that all-go-and-no-slow semIROCket was definitely one of the white-knuckle experiences of my life! At some point, though, the two-to-three seconds of waffley and (at best) only moderate stopping power they provided before fading into oblivion, no longer bore repeating. I installed a complete power front disc system scavenged from a ’72 Nova (back when they could be found at the local Pick-Ure-Part), and never had to look back at what I’d just run over!

I never did install a rear disc setup on that car, because the rear suspension wasn’t really up to the speeds I’d have been able to maintain with the additional “anchor” they would have provided. I don’t think the CHP would have been “up”, either! Could have been fun for a while, though.

So, at any rate, it would have to be said that I have given drum brakes a fair shake—maybe even going above and beyond the call of duty.

I have concluded that—purely from a PERFORMANCE standpoint—while a four-wheel drum brake setup is completely unacceptable (eventually, all auto manufacturers had to admit this), a front disc/rear drum setup did, in fact work adequately (within civilian boundaries) on my ‘bird—and, more importantly, for many of my customers. When it comes to braking systems, though, I’d really much prefer “great” over “adequate” for my use, since there are those times when only great truly gets the job done.

From a MAINTAINANCE standpoint, however, the rear drum system is ultimately inadequate, as it requires a lot more time and attention than a rear disc system.

How about so-called self-adjusters that generally DON’T (enough), even when all else is cleaned, lubed, set and functioning correctly? Or the required frequent drum removal to clean out trapped lining “dust”. And God help you if you have to remove a drum that has experienced “metal-to-metal” contact for some time (As luck will usually have it, the self-adjusters will, in this case, work well enough to extensively advance the process, effectively trapping the drum around the “imbedded” brake shoes. To make matters worse (if Murphy’s Law is in full effect) there will be no adjuster access ports in the backing plate, so the shoes can’t be retracted; meaning that Brute Force and Ignorance, or BFI, will have to be resorted to in order to remove the drum!).

In the end, when all is repaired and fully functional, you’re still left with an inefficient, complex and maintenance-intensive contraption. Egregious, undoubtedly!

The Interference Engine
Wherein engine damage occurs in the event that the camshaft and crankshaft become sufficiently out-of-synch with each other due to drive system (either belt or chain) failure.

This reaction is not limited to Overhead Cam belt-driven systems, but it happens more frequently with them.

The Mother of All Interference Engine Damage Cases has to be any belt-driven “Blue Propeller” creation. To say that these engines could be “damaged” with the advent of belt failure would be like saying you could be “injured” if your parachute fails to deploy while engaging in Skydiving!

The irresistible force of the crankshaft’s rotating mass behind the connecting rods and pistons, meets the immovable object in the form of valves and rocker arms made of some incredibly hard stuff, culminating in what is virtually an EXPLOSION within the engine. The resulting damage has to be seen to be believed: BROKEN pistons, BENT connecting rods, SCORED cylinder walls, BROKEN cylinder heads (from extreme lateral impact on rocker shafts, transmitted through the valvetrain)—almost a complete annihilation of the engine!

The fact that all of this mechanical carnage can be avoided if engineers just opt to incorporate a “freewheeling” engine design certainly gives me pause for contemplation.

I’ve seen engines of all stripes, from the economy-oriented to the high-performance sporting this consumer and technician-friendly design; so it doesn’t in any way appear to be purpose-exclusive.

All things considered, the interference design does indeed seem to have a reason to be… which is what qualifies it for entry into World’s Most Notorious Automotive Technologies.

Bin One being investigated, please return next week for Bin Two.

Phil Coconis is the owner of a West Coast independent  auto repair shop.

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55 Comments on “Memoirs of an Independent Auto Repair Shop Owner: World’s Most Notorious Automotive Technologies, Bin One...”


  • avatar
    Dimwit

    Why is Bertel’s byline on this?

    Interference engines, while a bane, also are more efficient because of the higher compression. The piston is closer, longer than a noninterference engine and remember, *every* diesel engine is an interference engine.
    Maintain your belts and chains and it’s not a problem.

    • 0 avatar
      stuntmonkey

      It’s not ust for compression rations, think VTEC and when the hotter cam kicks in with more valve lift.

      The problem with the timing belt change is that it creates a mini ownership crisis every 3-5 years…. do the belt and whatever semi-major maintenance thing or sell the car. It’s annoying, because you might as well go in there and do the water pump,etc. while you’re at it.

      • 0 avatar
        Syke

        So? My experience with interference engines are usually on cars that are something to drool over, lovely to drive, and worth keeping no matter what the expense is – assuming you can appreciate them in the first place. In that case, you either do the work or pay to have it done. Period. If you’re going to squeeze the nickle until it screams, you don’t want to mess with those kind of cars, period.

      • 0 avatar
        Athos Nobile

        “do the belt and whatever semi-major maintenance thing or sell the car”

        I remember a guy going through this with a Renault a couple of years ago. The timing belt replacement price was ridiculous and of course, a stealership only affair. So of course, a car with barely 60K kms, was “asking for money”.

        Timing belt is just another maintenance item, like the serpentine belt, oil, filters, shocks…

      • 0 avatar
        golden2husky

        ……Timing belt is just another maintenance item, like the serpentine belt, oil, filters, shocks………

        Think getting a T-belt replaced is tough for customers to swallow? Try struts and shocks. My FIL owned a repair shop and you would be amazed at the intense resistance to changing these things. He was always amazed at the number of people who would shell out big bucks for their cars, yet balk at a strut/shock replacement. It is no surprise that half of all cars hit the bone yard with original struts. At least the interference engine gets back at the cheap owner with a big bill….

      • 0 avatar
        Perc

        “The timing belt replacement price was ridiculous and of course, a stealership only affair”

        How is a timing belt in any way a “stealership only affair”? Even the smallest of garages probably do a couple of them per week and any parts place will carry what you need.

      • 0 avatar
        nikita

        When the estimate for a timing belt replacement is $1200 (transverse V-6) is is not in the same category as an oil filter. Fortunately that was a non-interference engine so I am quite comfortable doing a regular condition inspection. Shops dont like to do real inspections, but would rather replace parts. That is partly the customers fault, because they dont want to pay for labor that does not involve changing a part.

    • 0 avatar
      Pig_Iron

      How about those zany Lada aluminum brake drums that only come off in shards?

      About interference, I was taught to NEVER design anything that could catastrophically fail. I always designed things to “fail safe” or better still, not at all for the expected life. That said, I know the engine guys have many constraints, and that the interference design is a calculated risk based on statistical assessments like how many sigmas of cushion before MTTF. Like others have said, a good belt at proper change intervals is cheap insurance.

      Incidentally, at one place I used to work, at the end of every year, we used to give out the “Bent Bimba Award for Engineering Excellence”. It was a bent pneumatic cylinder mounted on a plaque and handed out tongue-in-cheek to someone who had made an “oh-oh”. It was a good reminder of diligence during design and the value of design reviews.

  • avatar
    MBella

    Couldn’t agree with you more on the drums. I also can’t understand how drum brakes can be cheaper to manufacture then discs. They have three similar components that should have similar costs to manufacture. The rotor and drum, the caliper and wheel cylinder, and pads and shoes. The disc brake setup basically ends there, but the drum has so much more stupid crap to make it work, I just don’t see it. All those springs, “self” adjusters, brackets, backing plates. It does not make sense to me. Subaru also, since their cars have 4 wheel discs on all cars.

    • 0 avatar

      I think a large part of the resistance to disks on the rear vice drums has to do with the parking brake. A caliper can be cheap; one that effectively remembers where it needs to be and engages each and every time the parking brake is used is another altogether. Plus, in a market predominated by front wheel drive, the rear drums were “good enough” to outlast the warranty period. Those two things go a LONG way towards explaining the popularity.

      • 0 avatar
        MBella

        That’s an argument I guess if they use a drum style parking brake where it has a mini drum inside the rotor with all the stupid crap associated with a drum. The little screw setup when integrated into the caliper can’t add that much cost to the price of a caliper. It’s a screw with a lever.

  • avatar
    MeaCulpa

    As the mechanic writing this seems to be located in a rather warm climate he fails to mention the most “fun” part of a drum brake. The F**king freezing up, FWD car with rear drums in winter. Front wheels spinning, rear wheel frozen, makes for some great fun on the way to work.

    • 0 avatar
      HerrKaLeun

      drums have are “self amplifying” and in smaller cars you can get by without break booster. Well, not really, but for disks you really need a break booster. That is were the cost saving is.

      Obviously this only works for older cars that did’t weigh more then 2000 lbs.

      In semi trucks drums are (or were recently) still standard since developing such large pressures is hard. I think the Mercedes Actross in the 1990s was the first semi truck with discs for that reason.

      Edit: not sure why, but my response was for MBELLA above

      • 0 avatar
        MBella

        Like you said, even heavy trucks are going towards discs. The parking brake also has driven by spring pressure and released by the air. This helps justify the drum design since it would be hard to have springs that engage the brakes and pressure release them.

  • avatar
    golden2husky

    In rear drums’ favor is the basically built-in parking brake. I have found that the weak link of rear wheel discs is the Rube Goldberg parking brake mechanism. Don’t even get me started on the stupidity of electrically activating rear parking brakes. As a guy who keeps cars a long time, I see the electric parking brake as a future high dollar repair instead of a cheap cable that will likely last the life of the car without replacement.

    • 0 avatar
      raph

      The parking brake mechanism on my 09 Mustang is a pretty simple affair, but its a sliding caliper design and the p-brake cable simply acts on the caliper mechanically in the same fashion as the hydraulis would.

      Anyways, on GM’s light duty trucks (1500, 2500, 3500, et al) drum brakes were prefered for light towing activity over discs for whatever reason with discs being prefered for the heavy towing.

      I also never understood why drum brakes were cheaper to install by the OEs compared to disc. I suppose it had something to do with economies of scale more than anything else given how ubiquitous the technology was in the US.

  • avatar
    Wheeljack

    The only drum brake design I ever saw/experienced that was truly brilliant and simple to service (and it happens to tie in to a junkyard find from a few days back) was on the ’78 Fiesta I used to own.

    It was a completely different concept than the typical Bendix/Delco/et al American drum brake design – it’s hard to describe without a picture but it dispensed with the cable and guide on a typical Bendix style setup and used a series of levers. It used a lot less parts than the typical US design, and surprisingly enough the self-adjusters actually worked! After seeing this setup, I often wondered why Ford never scaled the design up for larger cars and used it over here. It certainly would have saved money in part count reduction if nothing else and it would have caused a sigh of relief for professional and backyard mechanics everywhere.

    • 0 avatar
      krhodes1

      The rear drums on my Spitfire are very, very simple as well. In fact they do not even have self-adjusters, part of my annual maintenance afternoon is to get out my special brake adjuster wrench and give them a couple cranks. They take a 1/4″ square drive.

      I do think that it is the self-adjusters (that often don’t) that give rear drums a bad name. They are certainly more than adequate on the rear end of FWD shopping trolleys.

      I have no problem with interference engines – change the *&^%*^& belt on time, prefereably a bit early! Maintenance is such a foriegn concept to so many people.

      • 0 avatar
        burgersandbeer

        I have heard of cases of broken timing belts and fragged engines even when the belt was changed on time. Rare I’m sure, but it can happen.

        Staying on top of your maintenance isn’t a guarantee, and the penalty for a failed belt should not be engine demolition.

      • 0 avatar
        Pig_Iron

        @ Wheeljack & krhodes1

        Both true, but I think the shift from chained OHV to belted OHC left many old time owners unprepared for the extra maintenance required. Early “modern” fours like the 153 Chev had tractor-like reliability. Change the oil and filters regularly, with the occasional tune up and you were good to go. Within 2 decades OHCs, belts, e-ingition, and EFI were all coming on strong. That was a lot for older techs to handle too. Mech techs have my empathy and respect – there’s a lot on their plate. Not to mention the the diagnostic code access barriers.

    • 0 avatar
      Phil Coconis

      In the future, I will cover some designs that have made and make servicing autos an actual joy. Having spent a lot of time on Honda products, I remember the rear adjuster setup on the ’80 – ’83 Civic models. Incredibly simple and bullet-proof reliable! After replacing the shoes, preadjustment of the mechanism wasn’t needed. As long as the drums were within spec, and the parking brake equalizer was set correctly, all you had to do after reassembly was step hard on the brake pedal a couple of times, and it was set perfectly!
      It was as good as it got for a drum brake system…

      Then there was the self-adjuster system on my Fiat. A completely simple idea from somewhere out of “left-field”, it was as ineffective as it was innovative!
      My memorable experiences with Fiat will also fill a couple of story submissions, at the very least!

  • avatar
    burgersandbeer

    This is a great idea for a series and generally well written, but please lose the all caps.

    • 0 avatar
      Phil Coconis

      B & B!

      ONE DAY, WHEN I HAVE PERFECTED MY CRAFT, I WILL “LOSE THE ALL CAPS” WHEN YOU ARE MY EDITOR!!

      (And thanks for the compliments and input. If you didn’t love me, you wouldn’t have bothered to post the constructive criticism!)

  • avatar
    Educator(of teachers)Dan

    Interference engines ARE a conspiracy man!

  • avatar
    pdog

    I assumed a mechanic’s hatred for drum brakes would have more to do with the fact that they require so little expensive service compared to discs. I just checked my records, and since replacing the wheel cylinders 9 years and 120K miles ago, my rear drums haven’t needed anything, while the front discs/rotors have needed doing every 40K.

    Others with my car have converted to rear discs. Maintenance definitely increases. The other downside is a significant increase in unsprung weight on the rear trailing arms, which screws up the handling quite a bit.

    I will agree that a four wheel drum setup is terrifying.

    Also, I assumed my mechanic must love my timing belts, with their 60K mile lifespan, high repair price, and potential for valve damage. How else would he pay for his kid’s braces?

    • 0 avatar
      MBella

      The Akebono ceramic brakes that GM as well as many others use can last well past 100K. Mechanics hate drums because they are a pain with the reasons the author stated. There are plenty of service to do on rear drums, clean and adjust, replacing locked up self adjusters, and leaky wheel cylinders usually aren’t that infrequent up here in the northern states.

    • 0 avatar
      Charliej

      I was never a mechanic, but I can tell you any technician much prefers a job that can be completed quickly. Then he can got on to the next job. Also, drum brakes are just a pain in the hands to do. Changing pads is so much easier. Why were you changing rotors? In my experience the rotors don’t need changing if the pads are changed before they wear enough to damage the rotors. The worst rotors that I have seen were on my 2006 Sprinter. Apparently Mercedes used soft iron to eliminate squeal. The original rotors were worn out when the pads were worn out. I replaced the rotors with NAPA parts and did not have to replace them again until the third set of pads were worn out.

      • 0 avatar
        pdog

        Old rotors were probably fine. I changed them because they’re cheap ($30 a piece) and I was in there doing the pads anyway. Not environmentally friendly, but I did at least bring the old rotors to the scrap metal place.

        Based on their complexity, I’m sure repairing drums takes longer than discs. So wouldn’t the mechanic just charge a bit more? As a DIYer, I’d rather deal with drums once every decade than discs every 2-3 years.

      • 0 avatar
        golden2husky

        I think I warp the rotors on every car I own by the time it pad replacement time.

      • 0 avatar
        MBella

        You should always at either machine the rotors if possible or replace them. New pads on old glazed rotors won’t bed in properlly and you will be left with lower brake performance as well as more squeaks.

      • 0 avatar
        jpcavanaugh

        I owned a lot of drum brake cars and replaced maybe two drums over all of that time. I have lost count of the number or rotors I have replaced, and NOT because used up pads dug into them. My 94 Club Wagon seemed to require rotors every brake job, and my 07 Honda Fit currently has a really nasty vibration from warped rotors.

        I still maintain that if you do not live in mountains or ford streams, a GOOD set of big finned drum brakes will do you just fine and will be a lot less expensive to maintain. That said, there were a lot of under-braked drum cars put out back in the day.

  • avatar
    MrFixit1599

    When I was in the Navy, I used to do alot of oil changes, timing belt, spark plugs, etc. for buddies of mine that needed the work done on their cars. My typical charge was they had to buy the parts and a 12 pack. The ONLY thing I ever charged a case of beer for was drum brakes. Even if you have all the correct tools and are experienced at doing drum brakes, expect at least one busted knuckle and a few choice cuss words every time you change a set.

    • 0 avatar
      highdesertcat

      Me too! I remember those days helping buddies at the Patrick Henry Village Housing complex near Heidelberg. Lots of scrapes and bruises. I ended up making a hook out of high-tensile steel wire for those springs that retracted the shoes.

      And honing the slave cylinders by hand with a hand-held drill? Since none of us had a lathe to turn inside of the drums, we ended up doing a drum-brake job twice during a three-year tour.

      The local shops on the economy would not touch any American cars nor would they turn our brake drums for us. Glad those days are over!

  • avatar
    Andy D

    I am calling BS on your indictment of ” Blue propeller ” belt driven cams . My Bentley manual suggests a 60K mile/4 yr belt change interval A full kit, Belt and tensioner is only 40 $ and I can do the job in my driveway in an afternoon. Adhering to a proper, maintenance schedule or base lining a used car eliminates breakage. It is a case of RTFM. Should the belt break most only need a used head to get them going. Timing chains come with their own baggage too. Breaking a guard rail has derailed many a chain.

    • 0 avatar
      eggsalad

      Let’s go back to cam-in-block cars that had timing GEARS, then.

      Except for my ’75 Volvo 245, where they used gears made out of bakelite, because they ran quieter. Damn thing turned into powder at 240,000 miles!

      • 0 avatar
        olddavid

        I hate to admit this, but I’m old enough to remember when all cars had the “bakelite” set-up. I’m actually really proud that I’ve managed to live long enough to see a need for the sixth digit on the odometer.My Father was a small town car dealer, and the salesmen’s demo’s had to be completely tuned, new tires,aligned and new brakes done at 6-8000 miles. But, like the Passat commenter, I am ALWAYS baffled by the German mind at work.The domestics have always been reasonably reliable electronically, something that seems to elude the European makers as a whole.Recent experience has me somewhat jaded as I was dumb enough to find a beautiful Carmine red Catera with 57k and every documented service receipt in a folder.For $2500. How could I lose? Who cools the engine oil under the intake manifold? Who came up with faux rear air suspension that suspends nothing? Who puts a single wishbone front suspension on a 3700 pound car? I should’ve kept the MarkVIII…and bought a case of goop for insurance. It’s always something…..

      • 0 avatar
        Wheeljack

        3 out my 4 cars have a “cam-in-block” engine, all of which have metal timing gears and work exceedingly well. I’d be perfectly fine with getting rid of these needlessly complex overhead cams with their belts or overly long chains that can be ticking time bombs.

      • 0 avatar
        Pig_Iron

        @olddavid
        I’m embarrassed to admit I’d totally forgotten about timing gear setups. Especially since I used to make some. (That plant still had QC control charts from the the 1940s(!) hand typed and Mineograph printed.)

        @wheeljack
        I agree that OHC setups may be overkill for road cars, especially in stop & go traffic. I think a low friction OHV design with roller lifters and roller rockers on shafts is a superior design WRT compactness, component and assembly costs. But then, I love the Buick V6, the amazing morphing Ford Cologne V6, the VW VR6 – to each his own I suppose.

  • avatar
    da truth

    For the most part, I agree with you about Interference Engines. I believe a car should only have an Interference Engine when the timing belt job isn’t a serious pain in the behind. I sold my ’02 V6 Passat because I was sick of having to remove the entire front end of the car just to get to the fragile belts and water pump. Even if you didn’t remove the front end completely, you still have to use tools to keep the radiator assembly from falling over and damaging a lot of expensive bits of wiring and hoses. That is at least a 7-hour job. Even then, you end up with a bad back from bending over the radiator support. It was either that or give my vacation money to expensive German Car mechanics. Either way, you lose quite a bit of coin. The first time I did that job, I nearly used all the curse words in my vocabulary. You have to really love those cars to go through that ordeal more than once. Stupid decisions like those have turned me away from VW for a good long while.

  • avatar
    xenoxus

    Well timed article. For the past several years I’d been on my brother-in-law’s ass to change the timing belt in his Prelude. Well, the car died on the I-5 over the Grapevine. Got the car towed home, and pulled the valve cover off of the H23A1. Needless to say, upon seeing shreds of belt, I told him he was completely and utterly screwed. Well, then I made the stupid offer to help him fix it. I felt bad for his stupidity. To my surprise, when I pulled off the head there were only 3 bent valves! That was the only damage. The head was warped, but that was from when he severely over heated that poor four, so I got a reman’d head and a belt kit and he was on his way. Lucky bastard. Had that been a VTEC engine, he wouldn’t have been so lucky.

    Proper maintenance is your friend! And yes, drum setups are terrible.

  • avatar
    ciddyguy

    I know a lot of people dislike drum brakes when pared to front discs for most situations that a typical driver may encounter, they’ve been fine.

    I used to do much more work on my cars than I do now due to a lack of a place to do said work but did replace the rear shoes on drum brakes plenty of times in my past.

    It was in the early 1990’s, I think that I finally bought the proper spring tool for drum brakes and have the little off set adjuster tool too. Just using that spring tool made installing the springs SO much easier and replacing said shoes suddenly became easier. That said, I agree, the adjuster mechanism doesn’t work as well as it could, but I do remember reading that if you back up, press on the brakes hard, that’ll reset the adjusters and to do this periodically, otherwise they don’t self adjust like you think.

    I’m in agreement that with timing belts, one should check them periodically and replace if they begin to show signs of wear, or near the recommended interval, or a bit before. I’ve personally not had a belt break on cars that had them, but my parents had one Honda that did, and we got fortunate that none of the valves got bent as the belt must’ve broken at that interval before any of the motor was at TDC so a simple belt replacement was all it needed. That was an ’85 Accord SE-i sedan and at about 1990 or so.

    But I agree, an interference motor is a disaster waiting to happen, especially if the belt breaks prematurely, which it can (and so can chains for that matter).

    My 03 Mazda Protege5 has 4 wheel disc brakes but don’t know what they use for a parking brake but whatever they use, it seems to work fine but I DO wished my car had 4 wheel ABS though (an option at the time).

  • avatar
    Spike_in_Brisbane

    I am surprised that nobody has mentioned materials in the brake evolution story. I am not a metallurgist or industrial chemist but I suspect that the technology did not exist in the earlier days of automobiles to design and build reliable disk brakes. They rely on disks of metal (or carbon or ceramics) capable of withstanding very high temperatures and the disk pads have to deal with the heat buildup with much less material than a half-circle drum brake shoe. Also, brake shoes used to rely on the superior properties of asbestos which is now known to create carcinogenic dust and so has rightly been banned from use. Is there anyone out there with the knowledge to dig a bit deeper into the materials aspect of brake evolution?

    • 0 avatar
      BobinPgh

      I believe drum brakes have been since the early days of autos, but didn’t disk brakes come from aviation? They were invented first for airplanes because they were lighter weight and more effective and then gradually made their way to the auto industry. I also read that the interference engines are made that way to reduce emissions and that is a side effect of trying to make engines pollute less.

  • avatar
    daveainchina

    I hear you on the drum brakes. they are complicated and nearly worthless.

    As for the argument about materials, that really doesn’t hold. Drums are MUCH worse at dissipating heat than disks. which is really what brakes do. So no matter what materials you are talking about drum brakes are the worse choice.

    I think this technology just comes from an evolution of the leather wrapped around a wagon brake drum to slow one of those down.

    Also you need hydraulic power to work disk brakes with enough power to stop a car whereas cables could work on drum brakes.

    As for interference engines, the only real issue I have with those is that if you make your car an appliance that people barely have to maintain and then add one thing for maintenance that is critical (timing belt/chain) Expect to see a very very high level of failures.

    Interference engines are fine, for people who understand the technology, for everyone else though they are a hugely BAD IDEA.

  • avatar
    luvmyv8

    I don’t get why some automakers are continuing to use rear drum brakes on some of their models. Recently I got a ’12 4Runner, though I was considering a crewcab Tacoma as well. The Tacoma would have been less money, but the 4Runner won out. Why? The 4Runner’s brakes felt good, good pedal feel and it stops in a jiffy for being a relatively large body on frame SUV. It has discs out back and they bite down good. The Tacoma drove well, was managable around town and having the bed would have been useful (eventually I plan on breathing life back into my dad’s ’72 Corvette and getting my feet wet in LeMons- not with the ‘Vette though!)but the brakes just felt somewhat “mushy”, it didn’t really ‘clamp down’ and it just didn’t inspire confidence. The Tacoma uses drums and you can tell. That killed it for me. The Tacoma was thusly “disqualfied”. Too bad, but I just don’t mess around with that kind of stuff. Interesting too is that nearly all trucks have gone with 4 wheel disc….. Tundra, F150, Frontier….

  • avatar
    86er

    I’m sorry to hear that mechanics find drum brakes a pain in the butt to work on, but I prefer them as I travel on a lot of gravel and the sand/rock getting into rear disc brakes (like on the Vic) is less preferable to the rear drums on my 1/2 ton.

    I’ve never heard of anyone servicing drums before discs, especially as now front drums are a thing of the past.

  • avatar
    MrWhopee

    It’s not as if disc brakes are without problems, of course. Many (cheaper) cars come with undersized, poor quality front disc that warped all the time. I don’t know if good quality, well sized drums are better in this case. At least your car won’t vibrate like a wet dog every time you need to stop from higher speed.

  • avatar
    jrhmobile

    Let me offer two that grind my guts to this day:

    1) Parasitic vacuum-driven controls.

    Whoever the genius was who decided to use engine vacuum to power all those Rube Goldberg-engineered pre-computer emissions parts, heater/AC controls, wiper drives, transmission regulators and Lord knows what else. When that idiot sold the idea to car manufacturers saying “Engine vacuum is free”, he should have been beaten about the head and shoulders. Repeatedly.

    That clown sentenced us all to cyclical replacement of various sizes of decaying rubber lines and cheap pot metal and plastic vacuum fittings and manifolds from heat, cold, oil, gas, earth, wind and fire. The periodic, but relentless, failure of all that sucking crap killed more cars in their prime than Cash for Clunkers.

    2) Cheap factory scissor jacks.

    I’ve prepared a special Hell for the engineers who designed the factory-provided cheap scissor jacks. Special recognition for the ones who offered nothing more than a notch in the top plate to twist and bust the pinch welds between a car’s rocker panel and floor pan while it kicks out from under the car and drops the chassis to the ground.

    For them? An eternity trying to change a flat 60-series tire and fragile alloy wheel under a Ford Mustang II with the empty promise of instant salvation if they can ever accomplish the task. Emptying the oceans with a teaspoon would be child’s play by comparison.

    • 0 avatar
      Steve65

      “That clown sentenced us all to cyclical replacement of various sizes of decaying rubber lines and cheap pot metal and plastic vacuum fittings and manifolds…”

      Hey, count your blessings. I drive a diesel pickup. I’ve got to replace a vacuum pump. Which is present to create vacuum for all those vacuum-operated doo-dads you get to power for free. The CHEAPEST replacement I’ve found so far is $150+. And I don’t really want to think about how much 20 year old rubber hose is in there.

  • avatar
    indi500fan

    I worked hard are keeping my 67 Camaro faithful to its OEM state.
    But I finally gave up on the front drums, they were just too bloody difficult to keep adjusted for any kind of stable braking.

    Thankfully I was able to swap to OEM configured discs which at least theoretically could have been ordered on the car. The improvement was so big it’s hard to even explain.

    As for non-interference engines, back in the era of 8:1 or 9:1 compression, that wasn’t too tough to achieve. Now that everything is 10:1 or 11:1 compression, interference is just part of the cylinder/head geometry needed to get there.

  • avatar
    noxioux

    You hit the nail on the head on both of those nasty little things. My first adventure with drums was long before the interwebs. I had stupidly disassembled both sides at once. It was not funny at all.

    The whole interference engine thing really irks me. Having the life/death of your motor hinging on nothing more than a big toothed rubber band is just plain stupid. I’ve heard the excuses, none of which pass the smell test.

    BTW: It’s stupid easy to convert rear drums to disks on the old 10 and 12-bolt GM rear ends. Brackets, calipers and disks will swap directly from a 3rd Generation F-body (except for the metric connectors for the brake lines). I pulled the disks for the rear of my 68 Camaro from a dead 85/86 WS-6 Trans Am. Fits my old 10-bolt like a glove.

  • avatar
    icemilkcoffee

    It’s complete nonsense that drum brakes are worthless. I have a ducati single with drum brakes which stopped perfectly well. (Granted the sub 300lb weight helps). I’ve ridden BMW and Triumph bikes with twin leading shoe drum brakes and they stop extremely well.

    Too bad the twin-leading shoe design never made it into cars. They work well and feel great.

    The real problem is people using their brakes too much. On the street people are sprinting from stop light to stop light and using their brakes and gas unnecessarily. On the track people use the left foot braking technique with the right foot flooring the gas all the time. Of course you’d need a 13″ vented disc. The new style of CVT’s have almost no engine braking. Just quit using the brake so darn much, use engine braking whenever you can, and drum brakes are perfectly fine.

    • 0 avatar
      Phil Coconis

      For the speeds that Ducati is capable of generating, a drum brake is probably all it needs!
      On my Suzuki TL 1000 S, though, drum brakes would probably be more useless than they were on my ’67 Firebird!. In fact, I upgraded to the 6-pot front calipers from the “R” model in order to provide tuly confidence inspiring braking. As I said, I prefer GREAT brakes, especially on my two-wheeled conveyances!

  • avatar
    Racecar spelled backwards is racecaR

    Recently replaced my wife’s older VW Passat with a new one. Diesel or 2.0 direct injection gas turbo? Went with gasoline because it uses a metal timing chain (huzzah!) versus the diesel which uses a timing belt. 100% of the theoretical fuel diesel fuel savings are more than lost due to the added scheduled maintenance!
    Just this week I paid to replace my year 2000 Audi A4 1.8t quattro’s timing belt, the second one in 12 years. That, leaking injectors, replacing all the air injection tubing which got cooked, new clutch and flywheel (single, not Audi dual-mass), plugs, filters, didn’t need a water pump (whew), the second dipstick (plastic fittings gets destroyed by engine heat) came to $4,500. YIKES! The clutch and flywheel alone was $1,500 in parts and labor due to the quattro system. Though undoubtedly expensive, I figure I’m still ahead because I love driving it, and replacing it with a new car I’d like as much would be super costly. And a used replacement? Well, I know how well I’ve taken care of this one. As long as it doesn’t blow its engine or have a big collision/get stolen I expect it should be fun to drive another 5 years or more. Next up: bodywork and wheel refinishing.

  • avatar
    Onus

    Little car drums don’t seem to bad. Try changing 1990 f250 drums. Huge 12 inch and 3 inches wide. They also have these horrible shoe hold down snail springs that you need a super human just to get in. Still don’t know how i got them in. They are also covered by the e brake lever.

    Plus the drums way a TON. I did put everything new on them and the stop dang good. Self adjusters seem to work for now. But, it takes me HOURS to get the things, off and fix, and you bleed, and swear… ALOT.

    This is the reason i am never buying a car again with drums anywhere. I can do a disk job in 20 minutes on a 3/4 ton and most of that is taking the wheels off. The internal drums behind the disk on newer trucks looks so much easier in comparison.

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