Is this normal?

[Adam230K]

My car has been doing this for a while, but it doesn't affect anything in the ride, its just slightly wierd. Sometimes it makes a loud "Bang" sound, and it sounds like its coming from the back of the car. This sound only happens when i'm shifting in 1st or 2nd, and sometimes when i try to engage the clutch it does it too.

Has this got anything to do with that magnetic clutch thing? could someone shed some light?

 

[Sp!ke]

Is it a mechanical noise like a thud suggesting worn bushes or driveshaft mount or like a pop suggesting unburnt fuel igniting in your exhaust?

 

[Adam230K]

Its more of a THUD, which bushes would be worn and how does it result in a thud anyway?

 

[wile_e_coyote]

This sounds vaguely familiar, not on any Merc I've owned but on othe cars I've owned over the years.

It could be the uiversal joint at the far end of the prop shaft. When the needle bearings finally disintegrate, there is a lot of play in the UJ which you hear as a 'clunk' when the engine is taking up the drive, either when changing gear or more often as you let the clutch out when setting off.

 

[television]

Just jack one rear wheel on level ground with the parking brake off and in P.
Then rotate the wheel both ways and all play in the drive chain can be seen and heard, not forgeting the center UJ and surport

 

[grober]

More than likely its a worn component in the drive train as previously suggested. It could also be due to worn mounting components that support the drive train. The flexible mounting in the centre of the split propshaft is one possibility. The other possibilities are the differential mountings to the subframe or even the the rear subframe mountings themselves( altho with the subframe mountings there's normally a slight sensation of movement also, especially on the overrun)

 

[Adam230K]

This sounds vaguely familiar, not on any Merc I've owned but on othe cars I've owned over the years.

It could be the uiversal joint at the far end of the prop shaft. When the needle bearings finally disintegrate, there is a lot of play in the UJ which you hear as a 'clunk' when the engine is taking up the drive, either when changing gear or more often as you let the clutch out when setting off.

Thats almost precisely what it is.

So what do you guys suggest to be the next step? shall i take it to a specialist to pinpoint the exact fault? and if it turns out to be any of the listed things, is it doable by myself and a experienced helping hand?

 

[Dec]

Not the same car but will give you an insight into one possible cause. As already said it could be a number of things, best to get car on a lift to inspect.
http://www.mbclub.co.uk/forums/showthread.php?t=36119

Dec