Severe Vibration after Transmission Fluid/Filter Change
 

Facts: 1989 560 SEL 90k Miles. Changed transmission filter and fluid using MB approved fluid. Had to rotate torque converter (TC) to find drain plug. To do this I rotated the fly wheel by inserting a small pry bar thru one of two holes just in front of the TC. I rotated the fly wheel counter clockwise (from a drivers stand point) until I could see the plug.

Now I have a serious vibration. It vibrates only when the wheels are moving, even when I'm coasting in netural, whether or not the engine is running. At a stand still, it moves between P-R-N-D perfectly and does not vibrate. When I raise the rear and put the car in either R or D it vibrates as well.

Other work done at the same time: Oil and filter change, plugs, plug wires, dist. cap and rotor. please, Please, PLEASE help. Thanks, mscotta

Next time you change tranny fluid, check out the MB maint. manual first. You rotate the engine clock-wise as viewed from the front of the car by way of a 27mm crankshaft nut. I'm not sure if you tore something up using a pry bar in/around the fly wheel?

Did you drain the main pan and the torque converter? How much fluid was put back into the system? Still wondering about what happened around your flywheel when you were turning the engine in search of the torque converter drain plug?

The next time I'll use the 27mm socket to rotate the torque converter (TC)... it only takes me once. I did drain the TC and it took 8-9 quarts to fill the transmission. I'm not trying to rule out anything yet, but the fly wheel is pretty tough and I was fairly gentle (but I'll never do it again!). My fear is I caused some damage when I rotated the engine the wrong way. The most puzzling part to me is it vibrates when I'm just coasting in netural with the engine off -- I'm only going 1-5mph. I really appreciate your reply and thanks. mscotta

msc - something don't sound right here. Based on your explanation I don't read anything that you did during the tranny service that should have caused what you are explaining unless you like knocked a balance off of the drivshaft or something similar.

Thank you very much for the reply, Jim. I had a hard time determining where to life the car using a floor jack. The manual reads to lift it at the "frame cross member", but I wasn't sure where that was. Is the cross member directly behind the oil pan? At first I lifted it by placing the floor jack directly behind the transmission oil pan, on a plate that had a rubber "gromett" bolted to its top that looks like it is protection for the drive shaft. Maybe I bent something, althought it doesn't look like I did. When I raised the rear end and put it in drive I could not see anything vibrating around where I lifted the car the first time. But, man is the shuddering loud and it scared me to get under it even though the front tires were blocked off. A N D why does it shudder when it's only coasting??? AAAGGGHHH!

This may be one for Ben's Workshop in Austin, Texas. I don't mind taking it in if I can't fix it. I just don't get what I might have done... I think I'm going to cry.... but that wouldn't be "manley", hahaha hahaboo hoo boo hoo!! BTW, this is a great board!

mscotta

uh oh
 

Directly behing the transmission oil pan ain't a cross member and I suspect it is where your problem lies. Did you really get the car off of the ground using that support - WOW if you did. I am sure that is where your problem is. What the exact problem is I can't tell without looking underneath but I suspect something that was never designed to support the weight of the front half of the car is either bent or broke. Sounds like the rear tranny support. Your flex disc is in the vicinity and I would start looking real close at the front flex disc. If you are lucky it will be just a flex disc and rear tranny support replacement.

Lifting the car by the transmission cross member could cause the cross member to bend. This might throw the alignment of the tranny/driveshaft out of kilter, possibly damage the flex disk.

Since the car vibrates when the rear wheels are turning even with the engine off, I suspect a driveline component failure. Flex disk, center bearing, alignment or even a bent drive shaft or a combination of all these.

Yes, if the flex disk is now bad, driving it could cause the drive shaft to come loose and beat the tunnel. If that happens, yes, you will have a bang up time when the air bag goes off. And yes, if all that happens, expect the insurance company to scrap the old girl.

I don't think the failure on the 560 I got had anything to do with lifting, it was simply the flex disk gave out at speed. Made a nasty mess of the tranny and tunnel but nothing an able DIYer can't fix ;). Current standing: Tranny back together, replacement drive shaft in, tunnel repaired and sealed inside and out, replacement shifter in hand (waiting for installation), blown crash sensor out, replacement waiting to go in and lastly for today - complete set of 15" alloys, with Goodyear Eagles sitting in the back of the truck. Soon as my FastLane shipment arrives I can button up the drive shaft (new flex disk) and install the shifter (shift rod bushings). So close to being able to move her under her own power - too bad I'm going on vacation in two days.

Thanks for being so nice to someone who did something so stupid. Yes, I did raise the car by the transmission cross member. I finally got under and saw where the drive shaft (where it bolts to the transmission) is rubbing up against the floor board. I am not driving it, nor will I, believe it or not I have that much sense, although I question it sometimes and I'm very embarrassed about what I did.

I'm not trying to belittle this problem, but it doesn't look too bad as far as things being torn up. Some of the rubber gasket along the out side of where the plates bolt together has been rubbed off by the floor board. There is still about 1/8" between the floor board and the plates. Both the bolts and the plates look okay. Now that we know the problem, may I have suggestions as to my next step? (Although I'm pretty sure it will end up at Ben's Benz). Thanks. Signed, "Red as a Beat". (M. Scott Anderson).

well scott if you wanted to do it yourself i would start by ordering a new crossmember and trans mount and then replace everything with some help of a friend it will save you $$$ in the end.

I think you should replace that flex disk too. If it has been rubbing, there might be other damage to the disk. $57.00 added to the total bill is cheap insurance!

If you DIY, a cross member, transmission mount and flex disk should about cover it.

Lesson Learned, hope we all can make note
 

Greetings,

Sorry for your misfortune but it's just another process in the learning cycle. These cars are hard to negociate as far as where to jack and where not to. I've just made it a point not to jack up nor place jack stands anywhere on a moving part at all. I use the rubber pads located behind the jacking points witha piece of wood as my flat contact point when lifting the front or the rear of the vehicle. Seems like Benz designed this for the floor hoists and figured it probably was strong enough to support the car with a floor jack properly applied to that area. Those supporting members are to hard to determine when they seem to appear to flimsy to support the weight of these tanks.
I'd change out the whole works in that area while I was tearing things apart anyway's. What's a few extra few bucks to renew the entire area when it will probably need it 10,000 miles down the road anyhow.


Charles

Anyone that has ever worked on a car has probably done something that they later consider stupid - just be glad no safety issues came up because of it.
Anyway, I agree - change the rear tranny cross member support and the flex disc and it is a diyer job if you take the time. Also, take a good look around the front and rear of the engine from the top. With the flex disc being in the area where you describe these areas ain't in the same location as when it came from the factory. Look specially close at the radiator connections.

Good Morning ;

Just a thought. If anyone knows the exact tools this man will need to do the job it might help him with his prep and help him to go through the whole job without having to stop to aquire them.

Brian

19mm socket and box for the flex disk bolts, 17mm socket for the 4 cross member bolts, same for the two tranny mount to cross member bolts I think. I.m not sure, but I think the tranny mount to tranny nut is a 19mm. He will have to support the tranny with a jack, be sure to have a piece of wood between the jack and tranny pan ( I use a 2x4 caddie corner across the pan). Will also need a prying tool, pry bar or large screw driver to separate the yoke from the flex disk.

Just one comment regarding the way the engine was rotated. Mscotta said he rotated it counterclockwise as viewed from the driver's position, then Mike Richards said it should be rotated clockwise as viewed from the front of the car.

That's the same direction guys!

Obviously that wasn't the problem, but I thought I'd point it out.