Drivetrain vibration

[stevesLX]

I replaced my clutch this weekened and now I have a vibration that starts at higher RPM's in 4th and fifth gear. You can really feel it thru the shifter handle and up thru the seat. If you push the clutch pedal in it seems like its worse. I did not have this before. I checked to see if my motor mounts were tight and they were a little loose from where the motor tipped back when I pulled the tranny. So I tightened them up but I still have the vibration. Any help would be appreciated.

 

[jammer84_03]

t/o bearing?

 

[ShortThrow50]

I would suspect that the driveshaft is at fault. Unbolt the thing off the read diff. and turn it to the next set of bolt holes and reinstall bolts. Take it for a ride. If it still does it, try it again until you get rid of the vibration. This same thing happened to me when I installed a aluminum driveshaft. Now all is well

 

[DEFWISH]

driveshaft in upsidedown..

 

[stevesLX]

I checked to see if I put my driveshaft back in the same way I had it bolted up and I did. My throw out bearing is brand new and I am not saying that thats not the problem but I really dont think that is causing this vibration. I had my driveshaft balanced a couple of months ago and they told me it was out 3 grams. So they put a 3 gram washer on it. I was looking at my shaft tonight and where they had it at it is no longer there./ They had it screwed in right up by the yoke where it goes in the tranny. But will 3 grams cause that much vibration up thru the shifter and the seat at 2500 rpms and above in 4th and 5th gear and also at high rpms if I push the clutch in?

 

[Darkwriter77]

I got the same thing after I swapped my clutch a couple of years ago. I'm thinking, at least in my case, it's an imbalanced flywheel, because it's the only variable that really changed; I used the same brand of clutch, made sure I torqued everything down in sequence to spec, marked the driveshaft with a paint marker before removing it (reinstalled in same position), and the tailshaft bearing and U-joints are still tight n' good.

Did you have your flywheel turned down, or did you replace it with a new one?

 

[ShortThrow50]

Its deff. not the tob. It cant be the flywheel either if it was fine before you did your clutch install. Im still leaning towards the driveshaft. I would still turn it to a diff bolt pattern and start from there. It is possible for the balance to be thrown off if your weight came off. It must have happened when you removed it. Bottom line, I vote driveshaft. Hell, if you have it off, you might as well get it balanced again

 

[Darkwriter77]

Different flywheel could = imbalanced flywheel.

Again, was it replaced, or just resurfaced? And are you sure you torqued everything down to spec AND in sequence? (Criss-cross pattern on the diaphragm and flywheel, pretty much the same as tightening wheel lugs.)

Is there any slop in the tailshaft bearing? Grab the yoke closest to the tranny and give it a bit of wiggling around.

Another possibility is that the input shaft and/or bearing might have been damaged during the re-install process, if you let the tranny's weight hang on the shaft while putting it back up in there.

 

[ShortThrow50]

Different flywheel could = imbalanced flywheel.

.

very true. Sorry bout that bro

 

[stevesLX]

Flywheel was just resurfaced and I didn't use the criss cross pattern on my flywheel but I never have and haven't had this problem and I would think if its flywheel imbalanced that I wouls have vibration all the time in every gear and not just 4th and 5th at higher RPMs and when the clutch is pushed in.

 

[Darkwriter77]

Mine does the same thing in 4th and 5th, but usually just when I'm lugging it down too low in RPM's (below 2000 RPM) or on the highway above 75 MPH.

 

[ShortThrow50]

Flywheel was just resurfaced and I didn't use the criss cross pattern on my flywheel but I never have and haven't had this problem and I would think if its flywheel imbalanced that I wouls have vibration all the time in every gear and not just 4th and 5th at higher RPMs and when the clutch is pushed in.

this is why I still suspect the driveshaft. Now its up to you to go and check the balance

 

[93 LX]

Since engine speed is independant of vehicle speed I would think this is related to the drive shaft. My reasoning is due to the engine going through the RPM band many times before reaching 75 mph. It happens in 4th or 5th gear at the same speed however engine speed would be different at that speed. Start by rotating the drive shaft 90 degrees until you find the sweet spot then you will be fine. Also check the yoke for wear as this too could cause vibration.

Allen