86 560SEL. I was wondering if there is any kind of maintenance that can or should be done on a drive shaft. Just got new tires, changed the control arm bushings, got an alignment and yet the car still shakes. Some guy told me that sometimes it could be the result of the drive shaft needing some work. I know the drive shaft is factory balanced and should be put back the way it was taken out but is there anything I could do to check the integrity of the thing.

Thanks for any input.

Jerry, Atlanta GA

 

if you lift up the car, put it to gear, and accelerate at 4th gear...can you see the offset movement?

this is the same way we tune the propeller. use a chalk or something if you cannot see it. move the chalk closer till it touches the rotating propeller.

please observe safety.

 

That seems dangerous sleepwalker, and more that I can handle since I do all the work in my garage and have no lift. But what you say makes sense because the car starts shaking at and above 65mph. I thank you again for your valuable advice and I guess this time I will have to take it in to the pros.

Jerry Atlanta, GA

 

sure... i also mean to have it check that way... they know what to do.

 

I have read that flex disks often go bad. I have found some for $50 and decided to replace them because I have noticed some play. Is there anything I need to know before dropping the drive shaft ( I have the CD but it shows nothing) as I am sure if not put back correctly could cause vibrations and maybe damage?

PS: Someone should start a sleepwalker fund. If he got a dollar for every piece of advice he would be a rich man.

Thanks everyone

Jerry

 

[sm=thanx.gif] for the best proposal FALCON900. am just a poor person... but now i feel rich already because i can somehow imagine

if such things can happen, i will post a complete maintenance manual here for all models. also repair instructions with graphics for simple jobs, service informations, recalls, tips and tricks, and all technical requests will get a prompt reply according to the right procedure... and not just my own idea. there will be more than that. this forum will get heavy traffic for i will quit my job and concentrate on these matters.

THE FIRST AND ONLY FORUM TO GIVE ALL VALUABLE INFORMATIONS ON THE INTERNET.

you also need a lift on replacing the flexible disc.

the front part of the propeller can move a little because there is a spline to allow this movement... just enough for the disc to slide out in a tricky way.
but if you still cannot take out the disc, you can either loose the center bearing (mark the position), or release the rear transmission support bracket (needs an extra jack).

the early signs or bad flexible disc is a harsh thud if you play the shift from "R" to "D" repeatedly.

 

As always you are right. It is exactly what it is doing, going into reverse is a painful and noisy experience. And I was told that changing the flex disks will more than likely improve the situation. I have a 3 ton jack and 4 stands for that kind of stuff, but I would not trust such a set up for running the car up to 4th gear and being under it with a chalk.

Thank

Jerry

 

Also could be the center shaft bearing which is housed in a rubber donut and deteriorate with time. Mine was bad in my 87 300D W124, and vibrated at about 60 mph. But it does sound like flex discs in your case!

 

I inspected them and see absolutely no cracks or signs of wear, but I read that sometimes one discovers more when they are out. If I do anything (which I need to)I will replace every part that goes bad so I don't have to go back to it. I also have decided to change to rubber mounts on engine and transmission to see if it would help and they need to be done anyway.

Jerry