Possible Transmission Problem, C280

[Dave Bailey]

My normally very smooth C280 has suddenly developed a bit of a problem. Progress is now marred by a slightly harsh tingling vibration coming thorugh the floor. It is inaudible, but can be felt easily enough. The car was running perfectly up until a few days ago, when the fun started. I had stopped at a junction near to home after my usual commute and noticed the vibration upon driving off. There were no dramatic events, one minute all was well, the next, I'm driving in a bag of bolts......
The vibration is not related to engine speed. With the vehicle stationary the problem does not present itself. I can blip the throttle either with the gearbox in neutral, P, R, or D & there will be no vibration. As soon as I start to drive off, I can feel it. Under way & at town speeds it is very irritating. At motorway speeds it is much less intrusive, possibly being obscured by road surface and engine noise etc. In all other respects the car behaves perfectly, gear changes are smooth, drive engages instantly without any strange knocks or noises. The engine pulls smoothly. I can't hear any untoward noises outside the vehicle. At this stage I have yet to crawl underneath to see if anything has fallen off. The vibration hasn't worsened either. has anybody had experience of this type of problem? All ideas & guidance gratefully received. While I'm hoping that the solution will be simple and cheap, I have a nagging suspicion that this will probably be "exbenzive"..... Also it really isn't much fun to drive at the moment

Rgds,

Dave

 

[Alex Argent]

Hi Dave,
Hmmmmmmm..............peculiar one!
I doubt if it's actually the gearbox itself causing the problem because you seem to suggest it only happens whilst underway. The first thing that springs to mind is a diff. problem or maybe the driveshaft rubbers. I understand that these can deteriorate with high mileages, but I would think as speed/gearbox changes take effect, that you would get more of a 'clonking' noise and a very rough 'take-up'. I suppose there's always the chance that one of them (there's one either end of the propshaft) has completely disintegrated, but again, if this was the case I would expect a little more than vibration through the floor, more of a total shudder effect.
Another initial thought was one of the engine and/or gearbox mountings shot, however again that would tend to be just as bad at standstill, if not worse.
Based on the fact it is only occurring on take up and around town, it sounds as though it could be a suspension fault. Mine feels a bit 'clattery' over a rough road and at low speeds, but I've already established this problem as front anti-roll bar rubber mounts knackered (a known weakness on the W202's), and they're being replaced next week.
Apologies for not being much help, but I'm certain there are plenty of other more qualified comments on their way.
Regards,
Alex

 

[Sp!ke]

I'm just thinking it may be an exhaust hanger thats freed itself or something and whilst under load it is vibrating on the chasss or body.

I could be way off but definately worth getting under the car for a look see IMO.

 

[Alex Argent]

Good thinking Sp!ke,
Why can't I think of the simple solutions first ?
Regards,
Alex

 

[jimmy]

I would suggest you check the propshaft rubber or 'doughnut' and the wheel balancing.

 

[Dave Bailey]

Thanks to all you Gents, these are very good suggestions. I'm going to get under the car in the morning and have a good look for anything obvious. I'll let you know what I find. One thing that did spring to mind on the way home though was the possibility of tyre wear being a contributing factor. I did have a problem with a Mondeo once where there was a rumbling noise from the back that sounded very much like a shot wheel bearing. The tyres were nearly worn out anyway, so I had a set of Yokohama AVS's fitted. The rumbling noise went away with the old tyres. As I do have a rear tyre that's getting worn close to the wear bars, I'll get a new pair fitted if I don't find an obvious problem under the car tomorrow. Following Jimmy's suggestion, I'll get all four wheels balanced at the same time.
Alex - I'd be interested to know how much the front anti roll bar bushes cost. I too get a bit of a clonk from the front end when traversing rough road surfaces at slow speeds.

Thanks again,

Dave

 

[Alex Argent]

Dave,
Not sure of the costs yet, but I had already decided to do it myself. The front ones (4 in total) look a doddle, however the rears are a little more complicated as I believe most of the suspension has to be taken out of the way in order to get the anti-roll bar out. Having said that, the noise is only emanating from the front, so I'm leaving the rear ones well alone.
I would guess at about £7 to £8 each (they're only a simple rubber 'sleeve' that slides onto the ARB) from Euro Car Parts or GSF, no doubt considerably more expensive from a dealer though. God knows what the labour costs would be at a dealer - again a total guess, but I would envisage around 1.5 to 2 hours labour.
I forget what model you have, I think that on the newer models the rubbers are mounted directly onto the ARB, and when they go it obviously means a complete new assembly. I read somewhere on here that this was a known problem on the early W203's. However, I'm sure that all the W202's are replaceable.
Have a good holiday!
Regards,
Alex

 

[andy_k]

when I changed my front anti roll bar bushes they cost £3.50 each from the stealer.

Whilst you are under there check the integrity of the "hangers" for the outer two bushes. They are a known weak point and are prone to cracking with a hairline crack soon leading to complete failure - cost about £12 each to replace.

Andy

 

[Dave Bailey]

Well worth changing the hangers as well as the bushes as a preventative measure then. Good tip.

Well, I've been under the car and given it as thorough an inspection as I can, given my limited facilities. The only things I could find were a loose clip on the plastic undertray (fixed with a cable tie) & a cable guide securing screw completely missing (fitted new screw). Neither of these would seem to me to be responsible for the symptoms I've been getting, but at least they've been fixed anyhow. I'm at least happy now that there's nothing really wrong with the car as such. I'll see what happens when I get some new tyres.

Rgds,

Dave

 

[Dieselman]

I would guess at about £7 to £8 each (they're only a simple rubber 'sleeve' that slides onto the ARB) from Euro Car Parts or GSF, no doubt considerably more expensive from a dealer though. God knows what the labour costs would be at a dealer - again a total guess, but I would envisage around 1.5 to 2 hours labour.

My W120 ones were about £7 each and included the link rods. Fitting 5 mins each.

My local dealer beats ECP every time on both price and quality.