a dumb suspension/axleshaft question

[superbeast1098]

I need to replace both of the axleshafts on my w123 300d. The drivers side is making alot of noise when I drive. I am planning on taking care of that sometime soon...

I have also noticed that the driver side rear suspension is sagging a bit as well. Could the sagging suspension cause the noise and problem get worse?

I havent had time to diagnose the sagging suspension problem yet, so Im not exactly sure which components are the culprit. I will have to find time to do that......

Anywayz.... Any advice would be greatly helpful.

[leathermang]

Springs wear out... take them to a spring shop and have the re arched.. or get new springs from MB... they are really very reasonably priced... you will be amazed at the improvement in feel and handling....
There are some good threads about this.....

[rmmagow]

I'm gonna get yelled at but... My 300d sort of had a squat to it, worse on the driver's side. Not bad but the rear wheels kid of splayed out a bit like a VW. Going past some Jersey barriers one morning I heard this godawful noise like my exhaust was falling off. The noise turned out to be the death knell for the axles, both were very gone. When I took them out both ends kind of flopped around and there was a lot of lateral play at both ends. I replaced them both with AZ rebuilds, less then 250 for the pair. These didn't flop at all and there was no lateral play. I put everything back together and lowered the car. It appeared to sit a little more proudly and the wheels were straight up and down. After driving the car for a bit I noticed it rode better and generally felt pretty good on the road. The car still sits nice and level now. I know that to most this won't make sense but it sure seemed to make a diff on my car.

[t walgamuth]

also check the big pressed steel lower a arm. they can rust out and fail allowing the wheel to tilt in at the top and soon after fall off (i presume). this is a serious problem if not caught right away. if it is the problem the only fix is to replace the big a arm.

i have done two on my 123's. i got the a arm cheaply from a small salvage yard and had them installed by my indy. total cost i believe was about $400 ea.

[Brian Carlton]

Originally Posted by rmmagow

I'm gonna get yelled at but...................... I know that to most this won't make sense but it sure seemed to make a diff on my car.

You do know that this conclusion is impossible, correct?

My explanation is as follows, and it closely parallels my experience with the 300SDL:

When the vehicle is put up on jackstands, at the jack points, and the wheels and suspension are allowed to hang from the body, all the rubber bushings now try to go in the opposite direction. The springs also tend to do this. So, when you first lower the vehicle, it now sits about 1.5 inches higher than it did when you first put it up on jackstands.

In the case of the SDL, I changed subframe bushings and differential mount and was thrilled to see the tail rise from 24.75 inches up to 26.5 inch fenderwell height. I was convinced that all the posts regarding bad springs were BS and that replacement of these rubber components was the cure to the sag in the back.

After a full two weeks, with me making measurements all the time, the back end has stabilized at about 25.25 inches. The new rubber components added between .50-.75 inches of height. However, clearly, the springs remain the culprit.

So, in conclusion, please wait two weeks and then come back and report on the height of the vehicle. The drive axles cannot affect the height.

[superbeast1098]

I know the axles dont affect the ride height, but if the suspension is sagging, can that affect the condition of the axles?(making a noisy axleshaft wear out faster?)

Thanks to everyone for the responses so far.

PS, the car has no rust on it, so I dont think that is a factor in the ride height.

[BruceMcC]

"I know the axles dont affect the ride height, but if the suspension is sagging, can that affect the condition of the axles?(making a noisy axleshaft wear out faster?)"

Nope. The CV joints can easily accomodate a sagging spring.

My luck with (4) A1-Cardone rebuilts (Carquest and I think AutoZone) and (1) rebuilt from Rusty has been terrible. I'd suggest good used axles or new ones from GKN ($330. at mypartscatalog.com).

Best Wishes,
Bruce McCreary
(2) '85 300Ds, '83 300CD
Snowflake, AZ

[Brian Carlton]

Originally Posted by superbeast1098

I know the axles dont affect the ride height, but if the suspension is sagging, can that affect the condition of the axles?(making a noisy axleshaft wear out faster?)

This is an interesting question. I have made some measurements on the SDL, and with the back end lower than the design height, the axle shafts are not parallel to the road. The diff is lower than the axles so the shafts are angled slightly upward. The angle is not all that significant, about eight degrees or so.

The joint can easily accommodate this angle without any problems, however, it may be possible that the joint suffers from increased wear due to the angle. Obviously, I cannot confirm this, but, it would appear that M/B has designed the rear suspension so that the joints do not have any angle whatsoever with a "typical" load in the vehicle. It will be interesting to see, after I change rear springs on the SDL, if the angle changes to the opposite direction. The diff may now be higher than the axles with no load in the vehicle.

[superbeast1098]

I too made the mistake of using a rebuilt axleshaft, and I got the proverbial shaft. Its just as noisy as the one it replaced. That was over a year ago. Im trying to find the least expensive axleshafts that I can (either new or used)...

[t walgamuth]

i think that if your cv joints are worn with the suspension setting at a particular height that if you load the car differently or if a bush failure causes it to settle to a different height the cv running in a different place could make some noise. i dont necessarily think that this is always a sign of imminenent failure... if the noise is not too loud.

i have had four or five axles replaced with rebuilts. my indy gets them i dont know where and they have been fine. if you need a source i can ask him where they come from. i also have used used axles and they were ok but i think that the chance of finding used axles in good condition is getting slim as the cars are now well over 20 years old.

[Dance'w'Diesels]

Originally Posted by superbeast1098

I too made the mistake of using a rebuilt axleshaft, and I got the proverbial shaft. Its just as noisy as the one it replaced. That was over a year ago. Im trying to find the least expensive axleshafts that I can (either new or used)...

My car needs axles. But when I do 'em it will be just once so I am installing brand new units. Some parts are not worth gambling with.

[Palangi]

Originally Posted by Dance'w'Diesels

My car needs axles. But when I do 'em it will be just once so I am installing brand new units. Some parts are not worth gambling with.

You might want to check the price first.

[superbeast1098]

yeah...... The new ones are over $300 each..... Rebuilt units are around $100 each, and im not sure about the used ones......

[rmmagow]

I think most rebuilds come with a lifetime warranty, the ones I got from Autozone did. They have over 20K on them so far and are still OK. The things were easy enough to replace that even if I had to do it again I'd only be upset if it was December. As for my earlier post about a seeming improvement in ride height, I'll abandon that thought (except from me:-) ).
Yeah, re-builds are a crap shoot. Used ones where you can actually either pull them yourself or check them out first would be a good bet. This way you can check the status of the boots ahead of time.

[pmi]

I just ordered a pair of axles from these guys - about $145/each plus $50 core. I like the fact that they don't use oversize components. We'll see.
http://www.cvjreman.com/MercedesBenz.shtml
BigMac