Car Vibration - 50MPH+

[msuhanek]

My 1991 ZR1 has developed a vibration that appears to be coming from underneath, feeling it from my seat and through the steering wheel that is also vibrating a bit when it hits 50mph and over. Tires and balance are new. I will be taking in next week but wanted to get some feedback first on possible issues to look at.:salute: Thanks for your help in advance.

[billschroeder5842]

As you mention, your tires and balancing are new... did this situation happen after the new tires? If so, your wheels are out of balance.

You also need to check your U Joints. If they have issues, you will vibrate like hell.

[msuhanek]

Thanks, should have mentioned car vibrated b4 new tires and road force balance which leads to ujoints possibly but car only has 61k miles.


Sent from my iPhone using ZR-1 Net Registry (https://siteowners.tapatalk.com/byo/displayAndDownloadByoApp?rid=90383)

[Racinfan83]

If you find it let me know... Mine has 20k miles and I also have a vibration over say 55-60. Well documented in the forum. I have tried 2 sets wheels and tires, balances, rf balance, had the trans out to replace pilot bushing and inspected u-joints then, they were fine. Added C-beam plates when putting it back together so that is even more solid. So I still haven't figured it out... One thing I have not been able to do yet is to get with the FBI guys up north and try a completely different set of known good tires/wheels. One of these days hopefully I get time to do that... :o:o:o

[Paul Workman]

If you find it let me know... Mine has 20k miles and I also have a vibration over say 55-60. Well documented in the forum. I have tried 2 sets wheels and tires, balances, rf balance, had the trans out to replace pilot bushing and inspected u-joints then, they were fine. Added C-beam plates when putting it back together so that is even more solid. So I still haven't figured it out... One thing I have not been able to do yet is to get with the FBI guys up north and try a completely different set of known good tires/wheels. One of these days hopefully I get time to do that... :o:o:o

BTDT...I think. I was getting a vibration - more like a "BUZZ" at speed. Did NOT go away when I shoved in the clutch, which lead me to thinking "drive shaft". So, I had a driveline shop install new SPICER U joints and balance the drive shaft. That CURED my "buzzing".

BTW, I have a set of stock wheels you can use for your testing. Lemmeknow if you want to borrow them.

[Racinfan83]

Mine is a definite shake. Totally feels like out of balance tires. Both sets I have have been balanced and rebalanced. Gonna have to bring it up there some day and try one of your guys sets and see if that fixes it or if I have another issue. My joints on driveshaft were tight as can be when I had it out...

Sent from my LG-H830 using ZR-1 Net Registry mobile app (http://r.tapatalk.com/byo?rid=90383)

[We Gone]

This may be way out there, but do you get the fly wheel rattle at shut down? I have seen the DM fly wheel go bad.

Most Z's have a rattle at start up till oil pressure, No worries.
At shut down it's flywheel, all stock Z's have dual mass flywheels most will have a bit of a rattle at shut down or springs in flywheel could be getting a little weak they are over 20 years old, again no biggie,when you do a clutch change deal with it then.

Pete

[Racinfan83]

Nope.

[Paul Workman]

Just going through the checklist:


Half-shaft U-joints
Wheel bearing(s)
Suspension bushings
...
...
...

[tonywy]

I had the same issue, drove me nuts. Tried everything, tires , balancing, a known good set of wheels from my 86. I even changed the steering rack. Sitting in the garage staring at the car wondering whats up I pulled the right front shock off. It would only travel about two inches and stop. Low miles car no damage on shock. Changed shock and problem fixed. Just when you going you saw it all. Good luck.

[A26B]

Has the driveshaft ever been removed?

[TealZR1]

Thanks to all for providing feedback - will take into a good driveline shop this week.

[aafc]

A friend of mine had a vibration problem at about 65-75 on his LT1. Tried the
all of the possible fixes. At last resort they checked the pinion nut (it was loose) replaced the crush sleeve, torque nut vibration gone.
John
1990 #2546 black/white
one of a few Auto eq (4L80E ) ZR-1's

[Tripler]

Interesting . Our 1995 has begun to vibrate quite a bit after 60 mph in the steering wheel also and really heavy after 75mph . I have ordered new u-joints and drive shaft u-joints which will be replaced in the spring . I will also look into the shocks also as you have mentioned . Good ideas guys .

Thanks

;) ;) ;)