il_signore97

Hi all. I'm a new member here. I've had my W204 for about a year now, and decided it's about time to join an MB community. MB vehicles have been in the family for a while now, but this C300 is my first MB vehicle personally.

Although I've been enjoying the car for the past year, it has been driving differently lately while on the highway. When pointing straight ahead, there seems to be a lack of directional stability, some bump steer (the car suddenly chooses a slightly different direction after hitting a bump), and stuff like that going on. Thinking I had a tie rod issue, I brought it in. The dealer says nothing is wrong. I went for a drive with the tech, who also says he can't feel anything wrong with the car (not that he paid very close attention or anything).

So I decided to lift it up myself and check it out. There does not seem to be any issue with the tie rods, as there is no play whatsoever when grabbing the tires at 9 and 3 o'clock positions. However, I did find this (you may have to turn up the volume to hear the noise):

https://www.dropbox.com/s/lhdbgkwd9x...eel%20Play.avi

It's definitely not the lower ball joint as I don't see any movement there. It seems to me that it's the hub/bearing assembly with the play in it (passenger side shown, driver is not as bad but still not perfectly tight).

Anyone see this before? My dealer, although very nice and usually helpful, loves to tell me nothing is wrong (seeing that my warranty is almost up). Personally, I've never seen a hub with this kind of play in it without at least hearing some kind of grinding noise to go along with it. As far as I can tell, there are no strange noises while driving and turning.

The car is going back in tomorrow to get the updated radius rod bushings installed as per the TSB that is floating around. I intend to have them look into this other issue once again as I am not satisfied that there is nothing wrong.

Thanks in advance for the comments! Appreciate any help provided.

Cleanbenz

Sounds like a bad wheel bearing indeed. I've had play without noise in several cars. I'd t
Ask them to put it on the lift and show them what you found.

il_signore97

Thanks for the reply. The car was dropped off this morning for the radius arm bushings, so I gave them a DVD copy of the video and asked them to look into it and report back to me. So we'll see how that goes. I'll update once I hear back from them.

il_signore97

Update for everyone...

The dealer replaced the radius arm bushings as they were supposed to. They also were able to replicate the play in the front wheels. To my surprise (I honestly had no idea), MB uses taper roller bearings in the front end of RWD vehicles (like mine). So the play that I noticed was just excessive end play that signalled a bearing adjustment was in order. Obviously that was something that I could have done myself, but since it was there, they did it for a reasonable cost. They did say that periodic adjustments with the front end bearings are necessary from time to time. End play is now set within spec to 0.01 - 0.02 mm as per WIS.

I guess I've been used to working on the sealed press-in units (or the hub/bearing assemblies) that most manufacturers use these days. The only taper roller bearings I have worked on are on my jet ski trailers!

I'm hoping that the radius arm bushings and the removal of the bearing end play will help to improve the on-centre steering feel of the car once again. Hopefully someone finds this info helpful...