"Dong" noise at rear

[Uncle Fester]

Seems to be when cornering and hitting a bump at the same time, or just hitting bump with rear nearside wheel.
Can't decide if it's to do with the exhaust, ar a broken rear spring.
The car sits level, and a can't see any damage to spring, but it has a Dong sound like a low bell, any ideas?

 

[BlackC55]

100% Broken rear spring.

Get them from Mb only and repalce in pairs.

 

[Uncle Fester]

Thanks Olly, MB only? any massive difference between MB and generic ones?
I need two new rear tyres too, so may have to wait till next payday........

 

[A-AvantGarde]

Definitely springs, very common on the W203.

Don't wait too long as it could cause more severe damage. Last time I had a spring go I ended up upgrading the suspension

 

[jimbob35]

100% Broken rear spring.

Get them from Mb only and repalce in pairs.

During my service it cropped up that one of the front springs had snapped and needed replacing, the official MB garage told me they didn't need to replace both, they could be replaced singularly. It was important to get the tracking done though.

I always thought it was weird them not to even recommend replacing them in pairs..

 

[sammo65]

Had this happen twice on a W202 and a W208, the dong noise was the rear springs and describes the noise perfectly.

 

[SilverSaloon]

the official MB garage told me they didn't need to replace both, they could be replaced singularly.

what condition was the other side spring in? if relatively new, then i guess it would be ok surely its two factors; ride hight (with old spring vs new) and the fact that if one is gone, the other is on its way out too....? but if one is already newer, than that may eliminate the need to replace both at the same time?

 

[Uncle Fester]

I have bills that came with the car that state one front spring was replaced about 15000 miles ago, the other front spring was found to be broken during the last MOT (about 5k miles ago) so although the garage recomended changing both, I felt that 10k on a coil can be considered almost "new"

I will however be replacing the rear springs as a pair, but would still like to know why MB springs are better than generic ones (and at substancially higher cost no doubt?), as it seems to be the MB ones that break fairly often........

 

[stwat]

Springs from MB are not that expensive at all.

 

[e320cdiowner]

there are are varies MZ spring stiffeness depending the weight of the car which again depends on what options you have . ie the factory works out the weight of the car with the options and then they work out which spring has the right stifness for the car.

so in theory if you change your options than you have change the springs eg adding a/c may make the front a bit heaver so a stiffer spring is used.

If go to the russian website and just put your chassis No It will bring the part No of your spring for your car. but if you put in the model number of your car it it will show you all the parts nos of the springs and the options for each spring.

This why I always buy MZ springs only . speaking from experience from my w124 the springs break due corrosion at the last 3 to 4in bottom end of it. so next time if i need a spring I will corrosion proof it.

 

[e320cdiowner]

alternatively when you order your spring from MZ you should confirm with them what options you have if they are not factory fitted , the dealers will have a chart to advise you which spring you require. the colour strips on the spring is the indication of the stifness of the spring.So if you are adding extra rear facing seats on your estate dont forget to check out with MZ if you need to change your springs.
I did notice the MZ spring only comes in black undercoat paint . so it may best to wax , oil or use two pack zinc chomate paint . this may be why the colourfull non MZ spring may last longer as Uncle Fester suggested.

 

[simplestu]

Thanks Fester & Everyone- this intriguing and annoying sound (bang, dong, rattle) on bumps & low speeding up/slowing - has been driving me crazy.
Taken interior rear & boot apart, under car nothing dangling- several 'professional' checks found nothing. This could be the answer.

 

[x332race]

The springs normally break right at the lower end where they sit in the spring support cup and it is very difficult to check or see that the spring is in fact broken.

 

[Uncle Fester]

I had the same thing with a VW transporter, same sound, turned out to be a spring, I have never had it with any of the French cars I've owned, I guess Greman springs just ain't up to French quality!

 

[thefast1]

I have had this the same said noise coming from the rear drivers side for a few months now but didn't really think that it would be anything to serious, but after reading this thread I went to MB garage and they confirmed that it was a broken spring, told me to change them in pairs, £50 each plus £300 labour to do the job, and that is with 20% discount for the age of the car, so calld me local indie and they have quotted £170 for labour if I supply the parts, so I think I may go down that route.