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Clutch or drive shaft?

3K views 23 replies 7 participants last post by  SHIfTHEAD 
#1 ·
So my 2002 has had a rear main seal leak of a year or more with no clutch slippages noticed. Drilled the weep hole at the bottom of the bell housing and just keep the oil level full. Today I was going on a ride and had a failure. While passing a vehicle the roll on had normal power and acceleration, about the time I passed the vehicle the rpms went to rev limiter like it had been knocked out of gear. I shifted gear and the same result. Pulled to the side and cycled from first to 4th and only a slight amount of forward power.
First thought was contaminated clutch but once I started thinking about it I’m wondering if my drive shaft could have failed. What would be the best way to check the shaft to verify it’s condition?
 
#2 ·
That sure sounds like the drive shaft. The clutch disk could have disintegrated or you could have stripped out the splines on the clutch disk but that would likely have no drive forward at all and probably would have made some noise along the way.
 
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#3 ·
The best way is to look at it. Remove the rear drive and you will know. Alternate is to put it in gear, cold and see if you can spin the rear wheel. The drive shafts tend to slip really bad when they go and are hot but the rubber cushion will re-fuse when it cools down. This will be a weak bond. Visual is still the best way. First one is bad.
 

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#6 ·
Well it was the driveshaft, no doubt about it. Once I moved the boot and shined a light in there I could smel it and see the rubber. Here is what it looked like when I pulled it out. I found a used one I’ll install once I finish drilling the weep hole and replacing the slave cylinder seals. I appreciate the direction.
 

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#14 · (Edited by Moderator)
The 25X40X6 OEM size seal is for the output shaft where the drive shaft connects. If you are careful, you can use the 25x40x7 as there is enough room for it BUT, this seal, either size causes many people significant heart ache because there is an oil hole on the shaft and a very small distance too deep and it will leak like a sieve. You can see in the pic how close the lip rides to the hole. No room for a mistake. The only way I know of fixing that without buying a new seal is to split the trans and drive it out form the inside. Anything else will damage it for removal. Take a look at the photos and decide if you want to take a chance on creating a leak where it was not. You can see one that is too deep and leaking and one that is installed correctly.

If you are looking for the seal inside the hole the slave cylinder goes in, it is 17x28x7 and the dealer seal has been upgraded to Viton ( orange) and I recommend you use that seal as it will hold up better to heat and to break fluid if ever exposed. There are pitfalls with that seal as there is an opening on the side of the housing again that will leak if installed too deep. SOMETIMES DIFFICULT TO REMOVE WITHOUT DAMAGING THE CASE as can be seen by one poor souls experience in the attached pic.
 

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#16 ·
So my 2002 has had a rear main seal leak of a year or more with no clutch slippages noticed. Drilled the weep hole at the bottom of the bell housing and just keep the oil level full. Today I was going on a ride and had a failure. While passing a vehicle the roll on had normal power and acceleration, about the time I passed the vehicle the rpms went to rev limiter like it had been knocked out of gear. I shifted gear and the same result. Pulled to the side and cycled from first to 4th and only a slight amount of forward power.
First thought was contaminated clutch but once I started thinking about it I’m wondering if my drive shaft could have failed. What would be the best way to check the shaft to verify it’s condition?
When the shaft gave out was there any kind of a pop or snap felt just as your rpm jumped?
What you describe is very similar to my issue I was pulling away from a stop and snap was felt and nothing no nothing engine runs perfect no go bike had no symptoms of clutch failure. Worst part I just got the bike this happened on the 4 ride.uhg
 
#18 ·
Yeah, this thread is a year old but his issue is current. If it is not making any bad clanking or other noise, then one of two things has happened, either the clutch disk disintegrated or the drive shaft did a burn out as pictured above. You won't know till you pull some stuff apart. Stop when you find the issue, it will be pretty obvious.
 
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