Rear axle clanks

[George Davis]

Hello All,

I hear a metallic clank or rattle from the rear axle when going over bumps, on the right side only.  No clanking at all from the left side.  I haven't found anything loose, handbrake mechanism is fine, and the torque arm bushings are new, so now I'm starting to worry it's internal and maybe related to the axle pivot mechanism.  Can anyone shed some light on this?  Is an axle rebuild in my future?

Thanks!



George Davis
'69 280 SL Euro manual

[KevinC]

George,

Not certain if its the same but I get a (clunk, but could be called a clank) with SOME downshifts (auto) and SOME speedbumps. Local vintage MB tech states "differential support shaft and bushings". Parts are not THAT expensive but replacement is apparently time consuming. Waiting til summer when seasonal customers are back up north and he will give me a break on his hourly rate. He found this as there was play up/down in the shaft where there should not be any at all.

-Kevin

Boca Raton, FL
1967 230 SL Automatic
670 Light Ivory
113 Bronze/Brown MB Tex

[Naj ✝︎]

Could the universal joint (half shaft to diff) be a suspect?

Devils advocate

65 230SL
68 280SL

[hands_aus]

George,
When I had my axle rebuilt the mechanic showed me all the old bushes. The Diff BOTTOM support bush was very badly worn. You might be able to assess yours just by using an experienced eye.
Also there are two metal sleeves that the RHS axle arm pivots on that could be worn too.
The two grease nipples pump grease into them using spiral grooves in the bushes.

If it is that Bottom bush you might also experience clunking of the auto trans when changing up Or down.

Have you checked all the rubber exhaust mounts and the rubber buffer (near the vent funnel) of the back muffler?

Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[George Davis]

Kevin, Naj and Bob,

thanks for the replies.  The pivot joints all seem to be tight.  Naj hit on my biggest worry, that the u-joint inside the axle might be bad, or the bolt that secures the yoke might be loose.  However, I talked to Dan Caron (Benz Dr.) yesterday and now believe it's probably not the rear axle that's clanking.  I'm going to focus on the exhaust system as the likely source of the clank for now.  Dan also suggested the rubber buffer for the rear muffler near the vent funnel, so I'll be looking for that soon.

Thanks again!

George Davis
'69 280 SL Euro manual

[J. Huber]

Hey George. I'm hoping its the muffler clankin'. I know that the rubber donuts eventually wear out or come unhooked. Good idea for all of us to check on them once in a while...

James
63 230SL

[George Davis]

Thanks James, I'm hoping, too!  Will check all the rubber hangers tomorrow!

George Davis
'69 280 SL Euro manual

[rwmastel]

quote:Originally posted by George Davis

Thanks James, I'm hoping, too!  Will check all the rubber hangers tomorrow!

I have a clanking exhaust.  I looked under the car several times and could not locate any signs of wear or contact.  It took the experienced eye of Joe Alexander to find the contact point.  I would bet Dan's correct that this is your noise.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[Richard Madison]

Here is a link to a thread discussing rear end noise.

It includes my msg about replacing the rubber mount accessible from the front of the trunk (boot).

This easy fix cleared up my rear-end mystery clunk.

Richard M

http://index.php?topic=1336