Bang from front suspension - W140

[benzguy1987]

Traveling about 60 mph on smooth road. Heard a "bang" and felt a shudder from the left front. Now the left front seems a little lower than the right. Car ('97 S500) seems to drive well and does not have any creaks, groans, etc. from the front. It does have some vibration around 52-59 mph - but that was there before the noise. Any ideas? thanks....

[ASaltyDog]

Originally Posted by benzguy1987

Traveling about 60 mph on smooth road. Heard a "bang" and felt a shudder from the left front. Now the left front seems a little lower than the right. Car ('97 S500) seems to drive well and does not have any creaks, groans, etc. from the front. It does have some vibration around 52-59 mph - but that was there before the noise. Any ideas? thanks....

You may have run over something and busted one of those big hydraulic bushings on the lower control arms. Tie rod adjusters may have come loose, or any one of about 13 solid bushings up there. I replace them as a group whenever one looks bad.

Finally, your vibration is either a tire weight slung off, your wheels are just shot (that aluminum they made those 140 wheels out of is awful). Or some idiot dealer/shop hauled your car in with the car strapped down with 10 tons of weight - tires now permantnely out of round.

Oh - check your shimmy damner, but that'd be my last place to look (too obvious)

[TMAllison]

Check to see if the coil spring or spring perch broke.

[ASaltyDog]

Originally Posted by TMAllison

Check to see if the coil spring or spring perch broke.

Certainly could be. If, however it was a spring, the car would be bottomed out - you'd know it.

If it was one of the rubber bushings on either end of the spring maybe.

I've never seen a perch broken on a 140 - just made so much better than the 124s. Like a broken spring, when the top mount fails you'll know it. And the bottom is sitting on the control arm so unless that's cracked.

How about your shocks? Bottom sits on a pin that could also break, top sits in the wheel well. Usually not much load on the shocks unless someone tried to "lift" it. Could also be the shock itself (internal)

[TMAllison]

Owning a W210, I would disagree.

[bhatt]

I had one front spring broken on my 1992 500SEL and didn't even know it. I even towed a 2000lb boat with the car before I found out it had been broken all along.

Mechanic showed me the spring (it was definitely broken) but the ride height problem wasn't visible to the naked eye, either before or after the repair. I'm sure it was different - don't get me wrong - but I just couldn't see it by looking casually at the car (it didn't lean in any direction).

The amazing thing is, the car handled just fine before I had the spring replaced! Even while towing a boat, I didn't notice a difference.

So definitely look at your front springs. I was told this is a very common occurrence with older W140's because they are so heavy.. don't know if it's absolutely true, but it sounds quite logical to me.