Vibration. - Page 2 - ZR-1 Net Registry Forums

32valvZ · 01-03-2009

My limited thoughts are these

...... You say it was since the last rip to the drags, hmm. The things that are stressed the most would be clutch, transmission, U-joints, axle shafts and their U-joints. I would probably add in the motor mount as well, but from your description, I'm not 100% sold on that.

I would think that maybe the pilot bushing or the input shaft bearings could be the culprit. I say that because its happening on hard acceleration.

It almost sounds like there may be a combination of problems. The hum can be wheel bearing related as mentioned, or still a bad U-joint. U-joints are hard to pin down sometimes because alot of times, they dont make it obvious that theyre bad, unless theyre totally shelled.

Well, thats my .02

rhipsher · 01-03-2009

The new clutch only has about 3000 miles on it. And after I installed it I had the transmission fluid changed and the guy said that my trans fluid is nice and clear and thats a sign that the transmission is in good shape. It shifts so smooth and easy and it grabs great. So I'm not so sure its the trans. But I do buy the wheel bearings point on the humming sound. So my money is on the u-joints failing or the motor mounts or both. Once I have my morning nukie I'll go look for it and let you know what I find.

Jagdpanzer · 01-03-2009

FWIW had a similar problem a while back and turned out to be a bad tire.

rhipsher · 01-03-2009

It could be a bad tire. Last saturday when I put the NOS upper A-arm on I took it for a spin and up to 130 it felt so bad that I decided to just back off before I ended up with a drive shaft going up my azz.

rhipsher · 01-03-2009

Ok here's some video. And when I say the drive shafts look like they have alot of play in them I meant running out alot. Maybe .05 at least. And when I read on the common issues part of the forum that talks about drive shafts and them running out only .002? There's no way in the world mine are. The main drive shaft runs nice and true comming out of the transmission but when it gets to the rear it starts to run out about .05. All the old u-joints are Spicer.
http://s301.photobucket.com/albums/n...LEWABLE001.flv

Polo-1 · 01-03-2009

pull the driveshaft, pull one cup off.wipe grease off the cross, is it smooth or does it have dents in it from the needles. You dont even have to pull the shaft all the way out of the car, just the diff end. These drive shafts have no angle to them and will "box car" the the u-joint cross, and flatten the needles.

01-03-2009	#11
32valvZ Join Date: Nov 2007 Location: Sunshine State Posts: 1,071	Re: Vibration. My limited thoughts are these ...... You say it was since the last rip to the drags, hmm. The things that are stressed the most would be clutch, transmission, U-joints, axle shafts and their U-joints. I would probably add in the motor mount as well, but from your description, I'm not 100% sold on that. I would think that maybe the pilot bushing or the input shaft bearings could be the culprit. I say that because its happening on hard acceleration. It almost sounds like there may be a combination of problems. The hum can be wheel bearing related as mentioned, or still a bad U-joint. U-joints are hard to pin down sometimes because alot of times, they dont make it obvious that theyre bad, unless theyre totally shelled. Well, thats my .02 __________________ [B]1990 #2815[/B] [COLOR="Red"][B]Red/Red[/B][/COLOR] Ported Plenum & IH (by Pete) Haibeck Chip Rebuilt FPR (by Phil) FIC Injectors Watson LT Headers 3" Stainless Works exhaust Lingenfelter Open Air Lid Bill B Built Transmission Shifter & C Beam Plates [FONT=Impact][COLOR=red]1992 [COLOR=black]#[/COLOR] 091[/COLOR][/FONT] [FONT=Impact][COLOR=#ff0000]Red/[COLOR=silver]Gray[/COLOR][/COLOR][/FONT] [B]SOLD[/B]

01-03-2009	#12
rhipsher Join Date: Aug 2008 Location: Houston 90 Red ZR-1 Posts: 2,320	Re: Vibration. The new clutch only has about 3000 miles on it. And after I installed it I had the transmission fluid changed and the guy said that my trans fluid is nice and clear and thats a sign that the transmission is in good shape. It shifts so smooth and easy and it grabs great. So I'm not so sure its the trans. But I do buy the wheel bearings point on the humming sound. So my money is on the u-joints failing or the motor mounts or both. Once I have my morning nukie I'll go look for it and let you know what I find.

01-03-2009	#13
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,661	Re: Vibration. FWIW had a similar problem a while back and turned out to be a bad tire.

01-03-2009	#14
rhipsher Join Date: Aug 2008 Location: Houston 90 Red ZR-1 Posts: 2,320	Re: Vibration. It could be a bad tire. Last saturday when I put the NOS upper A-arm on I took it for a spin and up to 130 it felt so bad that I decided to just back off before I ended up with a drive shaft going up my azz.

01-03-2009	#15
rhipsher Join Date: Aug 2008 Location: Houston 90 Red ZR-1 Posts: 2,320	Re: Vibration. Ok here's some video. And when I say the drive shafts look like they have alot of play in them I meant running out alot. Maybe .05 at least. And when I read on the common issues part of the forum that talks about drive shafts and them running out only .002? There's no way in the world mine are. The main drive shaft runs nice and true comming out of the transmission but when it gets to the rear it starts to run out about .05. All the old u-joints are Spicer. http://s301.photobucket.com/albums/n...LEWABLE001.flv Last edited by rhipsher; 01-03-2009 at 08:22 PM.

01-03-2009	#16
Polo-1 Join Date: Sep 2005 Location: Washington Posts: 955	Re: Vibration. pull the driveshaft, pull one cup off.wipe grease off the cross, is it smooth or does it have dents in it from the needles. You dont even have to pull the shaft all the way out of the car, just the diff end. These drive shafts have no angle to them and will "box car" the the u-joint cross, and flatten the needles.