Hammer Time: What's In Your Oil?

hammer time whats in your oil

Two hundred thousand miles.

It’s a beautiful moment for many a car owner.

As for me? Well, I admit that I cheated when I saw that number flash by in my wife’s car back in March. Like many an enthusiast, I had bought it used and was planning on keeping her daily driver for the long haul.

The question for me was, “How long would the long haul be?” Since I buy, fix and sell a lot of vehicles, and have deeply imbibed the fluids of wisdom at the Bob Is The Oil Guy web site, I decided to live my life on the wild side.

I performed an oil analysis.

What I got back was a smorgasbord of technical information, and one pithy summation that went like this.

“STEVE – 200,000 miles? Please! This engine’s still a spring chicken. Metals look great here, so assuming she’s still running well and you’re not having any problems, then there is nothing about this sample that seems troublesome at all. Averages are based on about 7,600 miles on the oil. You could run your oil a bit longer, for sure. The TBN is kind of getting low (it’s down to 1.4 and 1.0 or less is low), but the TBN tends to drop more slowly the more use an oil sees, so it might hang on at this level for a while. The viscosity was fine assuming you used a 5W/20. Try 9k miles.”

I loved the spring chicken part. Boy that made my day. However that whole TBN remark threw me for a loop.

And what in the heck was a TBN in the first place? The BAD number???

Well, that’s when my quest for knowledge became a great big time suck. I went here, and later here. It was that second “here” which truly opened my eyes to what that TBN comment actually meant, and why I probably don’t want to delve any deeper into the inner workings of motor oil.

My engine was great. Case closed. Barring any unusual events, I was good to go for many more miles. I could extend my oil interval to 9,000 miles from 6,000 miles with a synthetic blend. Or maybe I could do a full 15k with a high performance full-synthetic engineered for longevity.

Mobil 1 EP? Amsoil? Deep Purple? Sorry.

The sad fact is that my wife drives a common-as-kudzu Prius with a light foot, and enough driving distance for the engine to always warm up. The local shop charges $20 for a synthetic blend and a quality filter. My net savings would be maybe $5 if I did it myself once a year with synthetic (her car holds a little less than 4 quarts.)

I spent $25 to figure all this out. So much ado about nothing. It was time to take the thermometer out of the motor oil, and worry about one less thing in my life.

My technical results are highlighted here. In the world where enthusiasts have to deal with the economics of keeping a car for a long time, an oil analysis can help you answer the uncertainties of a valvetrain’s health. But chances are, if your oil is regularly changed and you use products that are API-certified, there are better ways to spend your money.

If your car quits, chances are it won’t be your oil’s fault.

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2 of 65 comments
  • SCE to AUX SCE to AUX on Apr 30, 2014

    I've only seen two engines internally ruined: 1. My friend's Dodge Intrepid 2.7, which spun a bearing at 70k miles. No surprise there. 2. My other friend's 95 (?) Buick 3.8, which spun a bearing when the plastic timing gear teeth sheared off, traveled to the oil pan, and he restarted the engine after repairing it without cleaning out the pan. This car had about 80k miles. Better oil wouldn't have saved them, but better engineering might have.

  • Terrence79 Terrence79 on Mar 31, 2017

    Great write-up. I'm using the Amsoil 5w-30 alongside the nano-based Everglide EGS and I'm pretty impressed with this combination. I'm happy using Amsoil alone before, but my mpg has increased when I started using Everglide. It made my driving smoother and quieter too. Oil is indeed a huge factor in the longevity of your car.

  • ToolGuy @Matt, let me throw this at you:Let's say I drive a typical ICE vehicle 15,000 miles/year at a typical 18 mpg (observed). Let's say fuel is $4.50/gallon and electricity cost for my EV will be one-third of my gasoline cost - so replacing the ICE with an EV would save me $2,500 per year. Let's say I keep my vehicles 8 years. That's $20,000 in fuel savings over the life of the vehicle.If the vehicles have equal capabilities and are otherwise comparable, a rational typical consumer should be willing to pay up to a $20,000 premium for the EV over the ICE. (More if they drive more.)TL;DR: Why do they cost more? Because they are worth it (potentially).
  • Inside Looking Out Why EBFlex dominates this EV discussion? Just because he is a Ford expert?
  • Marky S. Very nice article and photos. I am a HUGE Edsel fan. I have always been fascinated with the "Charlie Brown of Cars." Allow me to make a minor correction to add here: the Pacer line was the second-from-bottom rung Edsel, not the entry-level trim. That would be the Edsel Ranger for 1958. It had the widest array of body styles. The Ranger 2-door sedan (with a "B-pillar", not a pillarless hardtop), was priced at $2,484. So, the Ranger and Pacer both used the smaller Ford body. The next two upscale Edsel's were based on the Mercury body, are were: Corsair, and, top-line Citation. Although the 1959 style is my fav. I would love a '58 Edsel Pacer 4-door hardtop sedan!
  • Lou_BC Stupid to kill the 6ft box in the crewcab. That's the most common Canyon/Colorado trim I see. That kills the utility of a small truck. The extended cab was a poor seller so that makes sense. GM should have kept the diesel. It's a decent engine that mates well with the 6 speed. Fuel economy is impressive.
  • Lou_BC High end EV's are selling well. Car companies are taking advantage of that fact. I see quite a few $100k pickups in my travels so why is that ok but $100k EV's are bad? The cynical side of me sees car companies tack on 8k premiums to EV's around the time we see governments up EV credits. Coincidence? No fooking way.