What are the symptoms of bad axles?
 

I've got an '83 300D with 133,000 miles and a pretty serious issue. I have a very loud noise coming from what seems to be the rear of the car; like a machine gun only not as loud. As I slow down, the clanging slows down also. I replaced both rear sway bar endlinks hoping for a low dollar fix, but it didn't do the trick. There is nothing that is obvious when underneath the car. I took it to the mechanic and he couldn't find anything wrong from a visual inspection. I have taken him for a ride on two separate occasions, and OF COURSE THE NOISE WENT AWAY!!!!!! :mad: :mad: :mad: It comes and it goes. When it makes the noise, it does this until I come to a complete stop and then it goes away for a while. I'm in a pretty bad mood right now, so I would certainly appreciate some input from calmer heads. Any ideas on what this may be? I don't want to spend several hundred dollars on axles only to have the problem emerge when I finish. The axles boot closest to the differential is torn; the oil is in my driveway.

did you check to see if something may be hitting the driveline? exhaust hanger, etc....

Given the constant velocity joint boot is torn, and the oil is on the driveway, I would suggest you found the problem. When this happened on one of my W123s the first time, it was quite alarming. A loud snapping metallic noise that is related to tire rotation speed. And, if the boot is torn and the joint isn't getting noisy yet, it will. The joint is worked pretty hard and without lubricants it gets rain and grit and other street debris inside and goes bad quickly. Jim

Yes,

I checked everything and then the mechanic put it on a lift and went over it. He suspected the driveshaft (insert part name here), but it looked fine. I wish I could describe the noise a bit better. When it clanks, it sounds like two pieces of metal hitting each other if they were coated in undercoating. At 65mph, it's fast like a machine gun. If I get on the gas, the whole car vibrates. When I let off the gas, the vibration goes away, but the noise remains. The noise continues until I bring the car to a complete stop. It resumes about 15 minutes after I drop a mechanic off at his shop.

Edit:

Thanks Jim,

I don't mind changing axels at all. I just don't want to fork over money for un-needed repairs.

Not to hijack this thread, but my car has the same symptoms OCCASIONALLY, but only when accelerating, and only about halfway through second gear. It disappears as soon as I let off the accelerator, but returns when I start giving it fuel again. Sound like CV's to anyone? Thanks!

Just out of curiosity.....
 

...does your emergency brake work?? Have you looked inside of the rear brake disc/drums.....any loose emergency brake parts in there??

You indicate that your CV joint boots are intact, all 4 of them......

One ol' salt to another.....

SB

Even looks like we have similar tastes in carz.....

Yep,

I removed the tires to change sway bar bushings and checked out both brake calipers. I did the brakes a year ago, so they are in great shape. I just finished ripping out the rear seat and checked the rear shock installation just to be sure.

Aarrgghh!!

You have a bad cv shaft
 

I would be willing to bet you have a bad passenger side cv shaft. My car did the exact same thing, like 2 metal pieces covered in rubber hitting each other. The right rear axle is the one that gets the majority of the power put to it. They are usually the first to go. I run a salvage yard so I took a used and in good condition drivers side cv shaft from a 240 and put it on the passenger side of my car. It fixed the problem. You have a bad cv shaft. The joints inside the housing spin inside of a hardened metal body. When the boot tears, the oil leaks out and it is virtually the same principle as running your engine with no oil. It tears them up, creates "slop" because of the worn metal. That is the clunking noise you are hearing.

Sounds like going or gone CV joints to me. Ever hear a front drive car take off and sound like someone was spinning a large ratchet wrench? That is the CV joints. The sound is different from inside the car.

Axles
 

1984 300d Turbo 141,000
Install Diy 2 New Axles Low Price $131.00 Ea. High Price Ea. $468.00

i agree cv joints likely.

park the car so that it is not resting against the drive train. chocked and in neutral. get under the back and grab the axles one at a time. shake up and down. if there is any play the cvs are gone. change half shaft.

good luck

tom w

Thanks so much for your help folks. I have been staring at my reef tank for over an hour to sooth my soul (I was pretty pissed!!)

I'll get some parts on order tomorrow and will be looking for any insight as to make the job go smooth. I read several write-ups on this site already, so I'm pretty confident I can get both done in a day.

Rather than live with the frustation. The axel on the side with the torn boot has to come off anyways. These cv oil filled joints cannot live with a torn boot and no oil lubricant. If the tear is large enough stuff the cv joint with grease in there. If the tear is not large enough increase it to get the grease in. Use a push stick or whatever it takes to get the grease into the joint. If the noise is gone for a couple of days go get a good used axel from the wreckers. Do not pay very much though and install it. Very few of these cars land up in the auto wreckers because of failing cv joints. Let us know what you do. There are others posting with simular complaints. I like cheap conclusive tests myself. The grease alone is not a permanent fix. But is a pretty good test. As someone mentioned too much road dirt and grime gets in there without a good boot for the grease fix to be semi permanent. Although if you could seal up the torn boot with the grease in the joint you might get awhile. A lot depends on how much damage is in there. Since it is still quiet most of the time it may not be terminal yet. Also why drive it till it lets go. Then you may have a tow bill and perhaps land up at someones mercy to get it back on the road. I have had just about every type of cv failure in the past myself. My favorite was when I thought I could still get a few days but cranked my steering wheel and backed up. The cv joint balls parted company with the cv joint. It was a front wheel drive car. Sometimes the noises will go on for quite a while. Other times they just provide a warning and go out pretty fast. If you catch it quick enough sometimes it is just a lubrication issue. One design of boots is changable on these I believe. If you get a donar axel from a wrecking yard try to get the opposite side. That way you have a lot less worn areas internally to start out with when it turns in the new direction. Also if your mechanic saw the torn boot he may not have been aware that those rear joints are oil filled and not grease filled. If he knew the boot was torn and joint was oil filled and ignored it you might need a new mechanic. Even if grease filled it would not be something to ignore. That has to be fixed even if it were not the problem but logic says it probably is. The road dirt will destroy a grease filled joint as well with time.

Barry,

Ever hear the expression, "When it rains, it pours?" The noise began when I was on the exit ramp for training I was attending this week. In other words when I was 5 minutes from as far away from home as I was going to be. I made an attempt to go today, but made it the same distance (Yes, I'm pressing my luck.) Anyways, the car is in the garage, and disassembly will commence tomorrow night. I had planned a road trip to Jersey this weekend, but I'll have to scrub that idea. If they decide to take a dump, they will most likely do so about five minutes into my trip back. I did a quick calculation in my head and really didn't like the idea of paying several hundred more in towing bills AND parts & labor. I'm just going to suck it up and press on. My buddy is on his way over to deliver a car for me to borrow the rest of the week.

Edit:

I started a thread a few months ago when I noticed the ripped CV joint. They have been dry for quite some time now, so most likely, they are shot. I like the idea of the grease and probably should have done that when I saw the first drops of oil in my driveway.

A mechanic friend and shop owner has a long thin tubular attachment for the geese gun that he lubs the cv joints with. Its small enough to work up under the boot, Might be nice too have, at least for checking too see if the noise goes away.