Rear Axle Shaft Movement - PeachParts Mercedes-Benz Forum

fredyarvin · #1 04-28-2006, 12:57 PM

I have an 84 300D and have a question about the rear axles. The passenger side axle is firm, with only a tiny bit of torsional play, but the driver's side axle can be moved left and right a couple inches. Is this by design or is something very wrong?

Thanks

d.delano · #2 04-28-2006, 01:24 PM

I'd say you have a problem. Those halfshafts aren't supposed to move axially.

Diesel Giant · #3 04-28-2006, 01:25 PM

Yes that is NOT a good thing.

fredyarvin · #4 04-28-2006, 04:05 PM

After setting the car back down on it's wheels, I find that both the left and rear axle shaft will move back and forth about an inch. Not the end housings, which are firmly attached to the differential and the wheel assemblies, but the shaft inbetween. I hear a clunck as it comes to a stop left and right. Is there supposed to be some play to adjust for wheel movement?

Thanks

rhodes2010 · #5 04-28-2006, 04:38 PM

What is the mileage of the car (and of the axles if different) ?

F18 · #6 04-28-2006, 04:52 PM

Fred,
I hate to tell you this.....but its time to have the rear end rebuilt or replaced with a used one in good condition. There is no easy fix.
The bearings in the diff. and the half axles are shot. If the gears have not started to hone out the diff housing and the half axle not distroyed the bearing seats then you can probably have it rebuilt.
Don't shoot the messenger......
Its not safe driving it that way for too much longer. I have seen whole half shafts slide right out on the road.....

d.delano · #7 04-28-2006, 05:01 PM

And all rebuilt units are not created equal. The problem being that during the rebuild process, rebuilders grind on the spiders and other hardened surfaces, and grind the hard surfaces off. Thusly rebuilts don't last, as the metal-to-metal surfaces are no longer hardened metal, but softer metal. Beware of CarQuest and AutoZone rebuilts. Brian Carlton has the name of a rebuilder he trusts, and who takes special care to not grind off the hardened surfaces that are so crucial to a lasting rebuild. New MB axles are the only other option, and the best option, but huge $$$$$.

Brian Carlton · #8 04-28-2006, 06:17 PM

Quote:

Originally Posted by fredyarvin

After setting the car back down on it's wheels, I find that both the left and rear axle shaft will move back and forth about an inch. Not the end housings, which are firmly attached to the differential and the wheel assemblies, but the shaft inbetween. I hear a clunck as it comes to a stop left and right. Is there supposed to be some play to adjust for wheel movement?

Thanks

Apparently my colleagues are on crack today.

The axles are designed to move axially to allow for the compression of the suspension. If the axles couldn't move, they would suck the wheels inboard every time the suspension extended.

The performance of the axles is normal and you shouldn't worry any more about it.

F18 · #9 04-28-2006, 07:00 PM

Brian,
Are your really saying that when you jack up the car.... grab a rear hub and push/pull the axle in and out of your diff. one inch thats normal?
I admit that I have never worked on a Mercedes rear end...never had to!
But I have had to replace rear ends in other vehicles I have owned/restored.
None of them when they were in good working order including the 98 E300TD
I have now had any play in them.
I must be missing something...oh ya my crack pipe!

Brian Carlton · #10 04-28-2006, 08:03 PM

Quote:

Originally Posted by F18

Brian,
Are your really saying that when you jack up the car.... grab a rear hub and push/pull the axle in and out of your diff. one inch thats normal?

That's not what he is saying.

The ends of the axle remain fixed. One end is fixed inside the diff and the other end it fixed to the hub.

Therefore, the center section needs to have some axial play......about 1".....to function properly. If you grab the center section of the axle, and really shove it, you can move it back and forth about 1" between the CV joints.

If the axle is removed from the vehicle, it's easy to see this movement. On the vehicle, it's more difficult, unless you are looking for it.

F18 · #11 04-28-2006, 08:39 PM

Brain,

Yep I got a visual!...independent rear suspension and movement is between CV joints. So what do you think Fredy's "clunk" noise is when stopping .."left and right"....bad CV joints, worn universal joint, funky spring seat or something simple like shocks.

Brian Carlton · #12 04-28-2006, 08:46 PM

Quote:

Originally Posted by F18

Brain,

Yep I got a visual!...independent rear suspension and movement is between CV joints. So what do you think Fredy's "clunk" noise is when stopping .."left and right"....bad CV joints, worn universal joint, funky spring seat or something simple like shocks.

I already explained to you that the condition is normal. The clunk is the CV joint reaching the end of it's travel. I wouldn't think you could get enough speed in the shaft to cause a "clunk" but, if the shaft is really loose, I'm sure it's possible.

engatwork · #13 04-28-2006, 09:01 PM

Quote:

So what do you think Fredy's "clunk" noise is when stopping

Has he checked out the sway bar links? My opinion on 1/2 shafts is pretty much run em till you can't stand the noise anymore. They will be noisy a LONG time before they will leave you by the road and I can't say that the noise is a "clunk" when stopping. If I remember correctly they will make a racket when turning either right or left when they are worn out.

Brian Carlton · #14 04-28-2006, 09:02 PM

Quote:

Originally Posted by engatwork

Has he checked out the sway bar links? My opinion on 1/2 shafts is pretty much run em till you can't stand the noise anymore. They will be noisy a LONG time before they will leave you by the road and I can't say that the noise is a "clunk" when stopping. If I remember correctly they will make a racket when turning either right or left when they are worn out.

Jim, he has the clunk when he slides the center axle section back and forth to the stops.

There is nothing wrong with the vehicle based upon the current info we have.

pawoSD · #15 04-28-2006, 09:04 PM

The shafts on our '83 clunk all the time, and they've been doing it 20k with no problems....we just tested the car at 110mph (it topped out) with synthetic tranny fluid, wow does that help at high speeds! Much smoother and quieter!

My car's rear driveline is still in solid shape, it does have boots that are near their end though....Once I have some $$ I'll have it re-booted, as I believe the CV axles to be perfectly good....