Back again with more questions -

I pulled the driveshaft last weekend and looking at the u-joint today I find that it seems to have a "detent" in the central position, i.e. it takes additional effort to deflect it away form center in all four directions. There doesn't appear to be any looseness or roughness, however, throughout the limits of travel. I have noticed a mild low frequency resonant drone at freeway speeds. Could this be due to the u-joint?

Though it's not normally a serviceable part I understand that some driveshaft shops can install a new u-joint in these and rebalance them. Can anyone recommend a place in the L.A area of So. Calif.? Otherwise, are there any recommendations for online suppliers? I've found a couple so far; Driveline Service or Portland rebuilds them with a greasable, replaceable u-joint, and I'm waiting to get a quote from them, as well as some information on lubing requirements and whether the new joint is staked or if they cut a circlip groove or something. They warranty for 5 yrs. or 50K mi.

The other one is Driveshaft Specialist, Inc. and they replace it using a sealed u-joint. They claim that the greasable ones require lubing every 5k mi. to get any useful life out of them which would be impractical on the MB. They have a good comparison of greased vs. sealed u-joints on this page. They warranty theirs for one year, but with unlimited mileage, and state that thier joints typically last upwards of 125k mi. Their price is US $329 - $374, incl. a new center bearing and carrier, UPS ground shipping and the $60 refundable core charge.

Does anyone have any direct experience with either of these firms, or opinions about greaseable vs. sealed u-joints?

Thanks

Gary

Before you go to all that trouble and expense, you can probably get the vibration out of it, by simply putting a washer between the carrier bearing bracket and the body on both bolts. This moves the position of the u-joint just enough to get it away from the worn spot and will usually do away with the vibration.

Good luck,

you didn't say what kind of shape the rubber flex joints were in, I have torn them apart before, my 83 300d I did and used parts from performance probably 10 years ago, a pain but not impossible, my 86 I did the flex joints only at 125000 so far so good now 139000

He didn't talk about the flex disks because he has found the "notch" in the u-joint. That is clearly the cause of the problem.

Have a great day,

The universal joint on my car's driveshaft behaves similarly. It's looser in the center (in the range of angles in which it normally rotates when installed in the car) and tighter if you move it to a greater angle (outside the typical operating range). The transition point between the loose and tight zones is noticeable, but this behaviour doesn't seem to cause any problems or noise that I'm aware of - are you sure it is the source of the noise you mentioned?

__________________

1989 250TD Wagon 5-speed, 160,000mi ::: Dark gray metallic / black cloth
1984 190D-2.2 5-speed, 287,000mi ::: Silver-blue metallic / black MB-tex ::: SOLD

Unfortunately, I can't be sure unless I change something and the noise/vibration either goes away or doesn't change. It's just that I've got it off right now, I'm doing an extensive amount of work on the car and I'd like to take care of as many problems as I can before it goes back together. Pulling it off again at a later time isn't a major obstacle, but I'd rather be driving the car and enjoying it for a change instead of continuing to chase down problems. I think I'll recalibrate my fingertips and go back tonight and wiggle it around some more and try to figure out if there's any discernible play in the bearings. If there is, I'd rather repair/replace it now and not worry about it for another 150K mi.

I'd still like to hear about anyone's experiences with rebuilt driveshafts or these two specific companies (or any others you might know about) and opinions about sealed vs. greasable u-joints.

Gary

The front was replaced at about 130K mi. and the rear is still in good shape; no rips, tears or looseness that I can detect. I'm planning to replace it during this teardown since I've got it apart anyway.

Gary

I have used driveline service in las vegas for my truck and had good luck, but I don't know if they are related

I would not recommend just any old driveshaft shop for this particular shaft. It needs to be someone who has done them before.

I used a driveshaft shop in Arizona. I think the name was Bejer. They only do work for commercial shops, so if you don't have a shingle hanging outside the door you will need to find a shop to get it done for you. Their work is first rate. Most shops that do the joint on these shaft use an American car u-joint from an early sixties Ford Falcon. Bejer uses a much stronger joint.

Good luck,