"annoying" vibration - driveshaft bushing or collar nut?

[lolcantturn]

Hey guys. i have this "annoying" vibration, its not aggressive but rather a nuisance. It happens after 65mph+ , the furthest I took the car up to is 80mph where it still exists and its gets a little bit more aggresive. I drove the car 250 miles like this and expected my guibo to be destroyed but it still looked new. I've replaced
the pilot bearing
throw out bearing
guibo w/ new 12.9 bolts
Driveshaft bushing
new trans mounts
new CSB

The only things I can probably point out is that the bushing may be installed backwards on the driveshaft. Does anyone know how it should be installed?


there's a SOLID face to it, where the rubber piece is solid with the outer shell, and then there's a less solid face on the other side. I have it installed with the less solid face on the output shaft of the transmission. perhaps this is it?

My collar nut isn't tightened down at all, could this cause problems?

It's not my pilot bearing or TOB, there's no feedback on the clutch pedal.
CSB is installed correctly and has no signs of wearing.....

[cabriodster87]

Doesn't matter, all that does is center the drive shaft to the transmission output. The collar nut needs to be quite snug to minimize chatter, and lube the splines with some thick grease. GL

[lolcantturn]

I put some thread on the collar nut, not a lot as I have to take off my exhaust but an ok amount, I could definitely get more out of it.
Didn't feel a real difference hmm.

Are you sure that the guide bushing has no specific orentaition? I feel that the more solid piece has to join the transmission's output shaft.

Though I don't *think* it's coming from the guibo area, since I've driven 250+ miles and my guibo still looks new. I drove 15miles with no guide bushing and my guibo was destroyed in utter pieces.

[lolcantturn]

anyone have a clueeeeeee?

[PNWDan]

If its from a specific speed its not your drive train. RPM specific vibration would tell you it is while speed related is likely tires or something associated with that part. if you don't feel it in your steering wheel its in the rear.

[lolcantturn]

If its from a specific speed its not your drive train. RPM specific vibration would tell you it is while speed related is likely tires or something associated with that part. if you don't feel it in your steering wheel its in the rear.

That's what I'm thinking, but it doesn't really make much sense to me. I can feel it after 65-80 (80 is the furthest I went, it got a bit more aggresive and I didn't want to ruin my guibo). But then I can REALLY feel feedback from my shift knob. Nothing in the steering wheel however.

[lolcantturn]

If I haven't mentioned it I'm getting a lot of feedback from the shift knob at the mentioned speeds

[lolcantturn]

I got this vibration after I changed my transmission and clutch from a G240 to a G260. I put a brand new sachs oem clutch and new pressure plate and an M20 single mass flywheel (im 24v swapped). Alligned it with an allignment tool of course, new pilot bearing and TOB. New guibo as stated before. The vibration can be felt through the shift knob. I didn't have this vibration before!

[jlevie]

Did the old CSB have damage to the rubber mount? In almost all cases that is a sign of binding u-joints in the drive shaft. Which can cause vibration as road speed increases.

[lolcantturn]

Did the old CSB have damage to the rubber mount? In almost all cases that is a sign of binding u-joints in the drive shaft. Which can cause vibration as road speed increases.

I bought the car as a shell so I can't determine that. The u-joint was fairly smooth and free moving when I had the shaft out

[lolcantturn]

Took it out for a drive again today, the vibration makes the shifter move, If I put the clutch in it doesn't change, and it happens at every gear.

[bimmerteck]

Driveshaft could be out of balance or have been put back together out of alignment. Often happens when people do not mark the two halves before pulling them apart to change a CSB.

[lolcantturn]

Driveshaft could be out of balance or have been put back together out of alignment. Often happens when people do not mark the two halves before pulling them apart to change a CSB.

Silly response but....I've never marked the two halves and I don't think I've ever had a problem! Is it truly as important as you state? If so I'll rip my driveshaft out now haha

[lolcantturn]

can any conclusions be made from this video? This is at 80mph, where the vibration happens

yes my selector rod welds are LOL-worthy.

[jlevie]

The drive shaft should have paint marks on it to indicate correct assembly. It is important that the u-joints be correctly phased and that the drive shaft be assembled as it was when it was balanced.