[BenzSIN]

My W164 ML350 power steering failed. The car was undriveable, as the steering was extremely heavy.

The good folks at the MB Service Centre found that the power steering pump had an internal blockage and had to be replaced. It was an unusual problem. The car has 60K on the clock and (unfortunately) 2 months out of warranty. Daimler Benz refused to cover the replacement cost. That's $1200 out of pocket.

I wonder if any W164 owner has encountered a similar problem with the power steering failing. I went through the list of service recalls, but did not see anything related to the problem encountered.

Many thanks.

 

[roadrutz]

It is always annoying when a serious problem occurs just out of warranty. However, my experience with "Mercedes -- or whoever -- refused to cover the replacement cost" often means "We, the dealership, aren't prepared to make an issue of this with Mercedes." If you are a good customer, the dealership will often go to bat for you. I had a couple of expensive repairs handled by BMW outside warranty, but only because the dealer beat on them on my behalf. I am sure it would be the same with Mercedes.

 

[BenzSIN]

Many thanks for your comments, roadrutz. You are absolutely correct.

Over here where I live, the Mercedes Benz dealership provides the maintenance support, but warranty issues go back to Daimler Benz. During the warranty period, there was never any issue, including a recent replacement of an Airmatic strut (around $2,500). In this power steering case, they would have to go back to Daimler Benz as it was past the warranty period. To the MB dealer's credit, they have offered the next service FOC, including a Nano technology car polish included.

However, I feel that Daimler Benz should shoulder some responsibility. An internal blockage of a power steering pump is both unusual and something serious. It was fortunate that the steering failure occurred at a slow speed, as I was turning a corner. The steering felt like a ton of bricks - at least a 50kg effort to turn the wheels a small amount. Had it happened on a highway, or if driven by one of my kids who's a relatively inexperienced driver, the event would probably end up being a great testimony for the safety features of a Mercedes in a car crash!

Shall keep you updated on how things turn out.

 

[audimotion]

Wow...2500.00 for one airmatic strut. I hope our airmatic doesn't break outside of CPO. Thats alot of change for one!

Good luck w/ your steering issue

 

[audimotion]

oh and was there any symtoms leading up to the steering pump failure?

I see you mentioned heavy steering, but was that right before it failed or was it heavy for a while.

 

[BenzSIN]

No symptoms at all, prior to the failure. All was normal as I turned the corner, and then, I felt a slight thud through the steering wheel and the steering felt like it was stuck in one position. It was only after this that I noted it required a great effort to turn the wheel.

However, when I think back, there were a couple of occasions over the last 6 months, when I had felt a very slight thud feedback through the steering wheel whilst driving. Hindsight is always 20-20 vision, and I would describe the feeling like pressure building up in a pipe and then releasing suddenly. As it occurred only twice and everything seems normal after each occasion, I had put it down to the wheels slipping on the loose road surface.

The irony is that, as the Airmatic strut was replaced just 6 months ago, I was going to ask the service centre to check out the steering at the planned service appointment next week. Last weekend's event overtook all this!

Thanks for the interest.