xdsmx

Google has turned up nothing so I'll ask you guys. We have an 08 ml350 with about 80k on it. Recently took it from fl into the tn mountains and the power steering got weird. Kinda hard to describe but if we think of it like a clock, 1-2 would have PS, 2-3 would be hard (no ps), 3-4 would be smooth, and so on. Once back into Florida it was 100% normal. MB service tech checked for leaks (none) and the fluid was perfect. He said the rack is a common failure but I have no signs of anything wrong. A buddy of mine told me he's had a similar problem and it was the seals swelling at altitude and it was a sign of them failing.

Has this happened to anyone? Dealer quoted 2500ish to replace. Thanks guys

jsmith18

Something like that happened to my '08. At certain steering positions it felt very stiff and then released. I drove it like that from Canada to California (it was OK at centre) and then had it looked at. They said the PS pump was gone and replaced it. It was fine for 2 weeks until in the middle of a turn at a busy LA intersection I could hardly turn the wheel at one spot on the clock. Good thing my wife wasn't driving as she could not have turned the wheel. Back to the dealer and finally a fix. The U joint on the steering column shaft was gone. It would almost lock up in certain positions. The tech put in a vice to show me. I'm sure that's what ruined the first pump trying to turn the steering column. It's now been fine for 2 years.

xdsmx

Thanks for your input buddy. I'm sure that's much better than a rack replacement. Mine too is fine at center and is a pain in the *** driving around town and pulling into parking spaces. I'm assuming it's something smaller as I have no leaks and no loss of fluids. Ill report back when my Indy shop inspects it this week

jsmith18

If it's the same problem and it sounds so familiar, be careful. I got fooled with the new pump as it had enough strength to overcome the problem until it locked up in the intersection and I almost ran into a couple of cars. Good luck and report back.

xdsmx

Lower part of the steering shaft was replaced, bottom knuckle was locked up. 229 for the part and 100 labor. All good now

jsmith18

Glad my experience could help you out.

xdsmx

That's why these communities are awesome. The mechanic immediately tried to replace the pump but I insisted on the forums recommendations.

jsmith18

But do keep an eye on your pump performance as the locked column joint took out my first pump before the found the real culprit.

N_Jay

Seems unlikely as the U-joint is on the input and should cause no extra wear on the pump.

rocky raccoon

I know this is a Benz forum but .....
Identical problem on my F150 pickup. Fixed by spray lube on the steering u-joint. Have to do it once-in-a-while (every couple years.

Btw, I have two Benz also. one of which is a 2008. Have yet to encounter this problem on it.

WhiteBlack

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