C180 Grinding Noise When Slowing Down Only???

[scots1]

Hi folks,
any help or knowledge on this would be greatly appreciated.
I have a Merc C180 Elegance, 1997 P reg 154k
Can drives as it should but....got a grinding noise coming from it only when slowing down???
Fine when under acceleration & no loss of power at all
doesnt grind when turning left/right thus that would eliminate wheel bearing problems, nor when braking which would eliminate Pads.

Any ideas or has anyone else experienced this problem??

 

[chelsw6]

I would jack the front up then, spin the wheels with my hand to see if the noise was coming from them, it could be something to do with the plate behind the disc, if not look at the back of the car doing the same , if its nothing to do with the wheels, brake area, you know to start looking elsewhere.

 

[television]

I would jack the front up then, spin the wheels with my hand to see if the noise was coming from them, it could be something to do with the plate behind the disc, if not look at the back of the car doing the same , if its nothing to do with the wheels, brake area, you know to start looking elsewhere.

Having had the same car with the same problem and that could be the brake back plate also, there is not that much on the car that can do this.

malcolm

 

[anyweb]

sounds like you could be talking about your catalytic converter,

most C series from that era at least have a cat, and when you decelerate (remove foot from accelerator) you can clearly here the 'roar' from the cat (that's when the cat is working ok).

I could be totally wrong (and usually am) but if this is indeed your cat, and if its making grinding noises then it could be breaking up,

i'm sure the experts here will advise accordingly one way or another

cheers
anyweb

 

[scots1]

Having had the same car with the same problem and that could be the brake back plate also, there is not that much on the car that can do this.

malcolm

cheers for all the replies so far but please kep them coming.

I'm very mechanically minded having been pootering about with cars for last 20 years but this noise is a boggler.
It passed its MOT in December without fault & i know the guys who do my MOT's & im positive they wouldve picked up on the brake back plates & the cat.

As far as noise goes.....it sounds like it is the brake back plate but im more than positive it's not, i did have the gearbox oil changed as an elimination thing but this noise aint got any worse & its not getting any better either.

I'm still interested in other ideas, i wouldnt assume it was the gearbox as there is absolutely no problems with it at all going up or coming down gears (manual 5 speed by the way)......

This is a baffler !!!

 

[anyweb]

can you try and find a road that's empty and straight and do some test runs on it with all 4 windows open,

listen for the location of the sound, even better have someone sitting in the back to see can they locate where it's coming from

just a thought

cheers
anyweb

 

[scots1]

can you try and find a road that's empty and straight and do some test runs on it with all 4 windows open,

listen for the location of the sound, even better have someone sitting in the back to see can they locate where it's coming from

just a thought

cheers
anyweb

Toooooooooo cold for that in Scotland just now, would much rather replace the gearbox than have windows open...especially all four of them :lol:
i have tried to listen for the noise when had drivers one down & dont hear anything.....i will give ur suggestion a try tho

 

[television]

Toooooooooo cold for that in Scotland just now, would much rather replace the gearbox than have windows open...especially all four of them :lol:
i have tried to listen for the noise when had drivers one down & dont hear anything.....i will give ur suggestion a try tho

The last guy here found that the spring that holds the brake shoes to the back plate had come off as the back plate had a hole in it. As you say would not get picked up by the MOT. There must be slight wear in the bearings after this milage,this would make it worse.

Try a slight presure on the perking brake to see if that stops the noise when it starts.

Malcolm