has any one had there pilot bushing go bad ?

[DISLEXICDIME]

has any one had there pilot bushing go bad ?

 

I am asking this because i have eliminated most my vibrations except when i get on it under load . It feel's like it is coming from the trans (this is the second trans and it is still doing it!). I am thinking maybe i chipped or smashed the pilot bushing one of the 3 times i have had the trans out .

[Z-train]

RPM specific or speed specific?

[ggzilla]

Yes ive had it go bad. It caused a sueak/squel when the clutch pedal is pushed down.

 

It is unlikely to cause a problem when your foot is off the clutch pedal.,

[datzenmike]

has any one had there pilot bushing go bad ?

 

I am asking this because i have eliminated most my vibrations except when i get on it under load . It feel's like it is coming from the trans (this is the second trans and it is still doing it!). I am thinking maybe i chipped or smashed the pilot bushing one of the 3 times i have had the trans out .

 

I would think that if it was really damaged enough for the input shaft to be off center (and thus the whole clutch disc would be wobbling), then it would would be vibrating at all times the clutch was engaged with the spinning flywheel and NOT be load dependent.

 

Take a good look at the tranny tailstock... is it centered properly and is it in line with the driveshaft?

 

In addition, the driveshaft angle (at the U-joint) in relation to the tailstock should be the same as the driveshaft angle to the differential. In other words, the two 'bends' at the front and rear U-joints must equal each other. Like this: (thanks BEEBANI)

 

http://i138.photobucket.com/albums/q251/datzenmike/Tranny/transdriveline.png[/img]"]

 

The driveshaft actually speeds up and slows down when spinning through a U-joint. Next time you have a driveshaft off lay it on a table an roll it while holding the spline end at an angle. You'll see that it does not turn smoothly but in a jerking motion. In a car with the motor at one end and the tires solidly at the other forces it to try and rotate at a steady speed. The acceleration/deceleration expresses itself as a vibration. Having two U-joints, (at the same angle) one accelerating and the other decelerating, will cancel the vibration.

Edited December 3, 2009 by datzenmike

[exit64]

If it happens under load but goes away if you engage the clutch it is a U joint going bad. A front one feels like a tranny problem. These kind of problems are a be-atch to figure out sometimes.

[hessianben]

I recently tore my tranny and clutch out of my Frontier because of a high rpm vibe when the clutch was pushed- especially when downshifting. it didn't feel quite like grinding, but more like if you had a long bolt in your hand, and were to spin a large washer on it as fast as you can- it would kind of buzz and vibrate.

long story short- pulled the tranny and clutch (wanted to upgrade to exedy stage 1 anyway) and i found a very mashed pilot bush.

i used a slide hammer and a flat head screw to extricate it.

tapped a new one back in carefully with a small piece of soft wood and rubber mallet.

vibration- gone.

[steve g]

i knocked a pilot bushing out once and it had a bad vibration at high rpm shifts or if i was holding 3500rpm or more under a load... the sound was like a scuffing sound between shifts..

[MicroMachinery]

I'm with the guys that say to check the u-joints. If you bust one of those puppies, it's NOT pretty. We're talkin', new driveline time, if you're lucky. If the vibration is only going down the road, you may check and see if one of your wheels might be imbalanced too. I'm not sure what the vibration feels like, so I'm just thinking of possibilities. Might check the transmission and motor mounts, as well.

[whitechef]

If it only happens when in motion it very well could be the pilot bushing.