Piston Slap: Self-Conscious About Your Rack?
Ronald writes:
Hi Sajeev,
Just about 2 years ago, the steering rack failed on my 1996 Lexus SC400 at 132,000 miles. Reconditioned rack #1 went bad in 3 weeks, and replaced with another. Reconditioned rack #2 also failed in about 2 months, and was replaced with a brand new rack.
Every time I got the car back, the steering feel was horrible even though they claimed they did an alignment (which they ended up doing every time I returned with the car). The last straw came when I was driving up a freeway entry ramp that had the pavement scraped in vertical lines, and the steering felt like a snake undulating left and right. Pissed, I finally took it to a Lexus shop where they performed an alignment and the car seemed to handle better. While satisfactory, it still was not the same as before the rack went bad. However, 2 weeks later the steering wheel was cocked to the left and the car was out of alignment. It went in yet again for an alignment at an independent shop and everything seemed fine – it was done better than by Lexus. Now two weeks after the latest alignment the steering wheel is cocked to the right and I’m beginning to feel the snake undulations again. What is throwing the car out of alignment? I live in Tampa, and the roads where I travel are in good condition, no potholes, I’m not running into curbs, and my wife doesn’t drive the car.
A few websites mention the control arm bushings, so I took it into an independent Toyota/Lexus repair shop that I found and have been happy with. They said they couldn’t find anything wrong.
One last thing: the rotors need to be replaced all around the car. The front rotors are warped, but I don’t know that that could throw the alignment off. I held up on spending the money for them because of the steering issues. I love this car and would like to keep it, but I’m at the end of my rope in dealing with it. Any help in the matter would be greatly appreciated.
Sajeev answers:
There are two problems presented: first is the insinuation that your wife cannot drive a car without throwing the front end out of spec. I suggest a date night with dinner and a movie for compensation. The second is the number of mechanics who didn’t replace a single bushing. The rubber on this car is positively ancient, it needs to be replaced. Many people drive older cars on occasion, unaware of the ravages of time on clearances and component decay, and simply assume that “The Good Old Days” were truly awful. False.
Putting a new (OEM) rack, new air springs, control arms, bushings in my ’95 Lincoln Mark VIII was a serious wake up call: all of a sudden the steering went from stereotypical Detroit land yacht to something disturbingly close to the heft and accuracy of a late-model AMG Benz. Did a similar transplant to our 1972 Mark IV: lo and behold, the yacht’s tiller gained the accuracy (if not speed in lock-to-lock turning) of a Camry LE. This isn’t a load of bunk, it happened.
So get serious: rubber and ball joints get out of whack after 10+ years and 100+k miles on the road. It’s time for a complete suspension rebuild, even if it doesn’t seem necessary. Rubber can look fine. Ball joints may not pop and knock in the middle of the night, but it’s time to replace damn near every moving part in the suspension.
Of course, if this was an undesirable vehicle, this is the time to consider scrapping it for something less claptrap-tastic. But a Lexus SC400? This is a no brainer, if you want showroom-fresh dynamics, you rebuild the entire front clip. And it’ll be worth it. Off to you, best and brightest.
Send your queries to mehta@ttac.com. Spare no details and ask for a speedy resolution if you’re in a hurry.
More by Sajeev Mehta
Comments
Join the conversation
From my experience 140K miles is pretty low mileage, nothing should fail at this mileage. 15 year is a long enough period of time though for rubber to deteriorate. So inevitably all rubber must be replaced after 15 years for sure. I know that tires must be replaced after like 6 years regardless of condition, even if car was not driven much. Shocks should be replaced probably after 100K. Of course if you want to keep car for long time and enjoy the ride. Regarding rack failure, just replacing failed part may not be enough because root cause of failure is still there. I had Ford Taurus bought used with over 100K miles. Its torque converter started leaking badly when get hot after couple of months and transmission was already in bad condition. I spend couple of grands to replace torque converter and rebuild transmission. Problem repeated after couple of month and after couple of years torque converter was leaking like same way as when I bought it. The problem was with slipping piston clutch in TC and to compensate it controller increased pressure in transmission which messed up the whole process of switching gears making it out of sync and etc. which in the end tend to ruin transmission. And of course hard gear changes also were wearing out torque converter prematurely and cause the leak in place where shaft connects to TC. I do not know what was the problem with piston clutch and why it started to slip while TC new (actually rebuilt). But I learned the lesson that if something strangely fails it will not be fixed by just replacing the expensive part because problem may be elsewhere and you need to make full blown research to find out if you have a time. Consider it as a bad karma and get rid of car while you can and buy another one of the same brand which do not have same strange problem, but pay attention to every detail to not end up with another nasty problem.
@MarcKyle64 If you're looking for a "I had one of those, and it was crap" story, well I had one of those, and it was crap. Mine was the same year, but with the straight six rather than the eight. I sold mine at 12 years old and roughly 110,000 miles. The suspension as far as I could tell was in good shape, and the drivetrain was holding together reasonably well, but the electronics were completely hosed. The car had constant starting problems, CELs were more frequent than not, and the O2 sensors seemed to last 3 months. Every piece of interior trim cracked, and the leather seats wore terribly. The headlights were always full of water (common SC problem) and eventually both lights had to be completely replaced. LS400s from that era deserve their bulletproof reputations, but the SC does not. I won't be buying another Lexus any time soon, not really due to my poor experience with the SC, but just because everything Lexus makes now is boring and ugly, with perhaps the single exception of the IS350. Even that though is barely average in a class of much better cars like the S4 and 335i.