Vibration

[TFENT]

So I have a 90 ZR1 with 31,000 on the odometer, totally stock except for a Marc H. chip. Also live in San Diego where we can open up the cars more then most people (ie 100+) on the freeways. So I took out the vette for a "Sunday" cruise this weekend (150 miles). The car has always had the Corvette creaks and rattles but anytime I am over 60mph there is a vibration that is irritating my beyond belief. The car has new tires and rims and I have had them checked like 4-5 times on a load match machine. They are perfect. Thing is this is my first Vette. I do not know if these cars have a natural tendency to have a high speed buzz or not. Since It was sitting a very long time in storage before I got it I am wondering if maybe the drives shaft(s) or U-Joints are bad/frozen or out of balance.

The buzz is just enough to cause the rearview mirror to vibrate enough to not see out of it. Its not real bad like a flat spot. Just as i stated earlier it's an irritating buzz. especially at 110 when I NEED the rearview mirror.

TIA for any suggestions.

[tccrab]

Could be U joints, but with only 31k miles they *should* be just getting broken in not worn out.
Has the transmission been out of the car recently?
When this vibration happens, can you feel it through the shifter?
Does the shifter lift under heavy acceleration?
If so, try tightening the C-Beam bolts, and if you don't already have them, order up a set of Bill Boudreau's (The ZF Doc) C-Beam plates.

My '90 is noisy at 100+ but no vibrations like you describe.

TomC
'Crabs

[TFENT]

Originally Posted by tccrab

Could be U joints, but with only 31k miles they *should* be just getting broken in not worn out.
Has the transmission been out of the car recently?
When this vibration happens, can you feel it through the shifter?
Does the shifter lift under heavy acceleration?
If so, try tightening the C-Beam bolts, and if you don't already have them, order up a set of Bill Boudreau's (The ZF Doc) C-Beam plates.

My '90 is noisy at 100+ but no vibrations like you describe.

TomC
'Crabs

Tranny has never been removed.

Little to no vibrations through the shifter

Shifter does not move under acceleration.

I will get a set of the C-beam plates.

Thanks Tom

[ZZZZZR1]

Originally Posted by TFENT

So I have a 90 ZR1 with 31,000 on the odometer, totally stock except for a Marc H. chip. Also live in San Diego where we can open up the cars more then most people (ie 100+) on the freeways. So I took out the vette for a "Sunday" cruise this weekend (150 miles). The car has always had the Corvette creaks and rattles but anytime I am over 60mph there is a vibration that is irritating my beyond belief. The car has new tires and rims and I have had them checked like 4-5 times on a load match machine. They are perfect. Thing is this is my first Vette. I do not know if these cars have a natural tendency to have a high speed buzz or not. Since It was sitting a very long time in storage before I got it I am wondering if maybe the drives shaft(s) or U-Joints are bad/frozen or out of balance.

The buzz is just enough to cause the rearview mirror to vibrate enough to not see out of it. Its not real bad like a flat spot. Just as i stated earlier it's an irritating buzz. especially at 110 when I NEED the rearview mirror.

TIA for any suggestions.

I agree with C beam plates, but...

What kind of wheels (OEM)? What kind of tires?

One thing that I have heard is to get them Road Balanced (not just the standard balancing).

[TFENT]

Originally Posted by ZZZZZR1

I agree with C beam plates, but...

What kind of wheels (OEM)? What kind of tires?

One thing that I have heard is to get them Road Balanced (not just the standard balancing).

A Mold Factory wheels w/ Nitto 555's (brand new)

I got them load matched or road balanced

[jonszr1]

you might want to jack up the rear of the car and ck your 1/2 shafts and your rear bearings as well as the bushings in the rear. sometime when a car sits for a long while things can start to go bad from lack of use

[TFENT]

Originally Posted by jonszr1

you might want to jack up the rear of the car and ck your 1/2 shafts and your rear bearings as well as the bushings in the rear. sometime when a car sits for a long while things can start to go bad from lack of use

The u-joints in the 1/2 shafts? What bushings?

[tomtom72]

Not trying to be a wise a$$.....but what setting on the FX3 are you using?

I ask because on setting 3 ( performance? ) setting my rear view along with the side mirrors are useless after about 130. This used to happen in the #2 ( sport? ) setting with the original shocks, and at #3 my eyeballs were vibrating. Okay the roads are proly better where you are....but just saying that the firmer the FX3 setting the more and sooner my mirrors bounce into uselessness.

The only thing with my experience is that I don't hear anything, it's just the chassis transmitting the road conditions, mostly bad, thru the rest of the car. It's enough to make you want to slow down.


Tom

[TFENT]

Originally Posted by tomtom72

Not trying to be a wise a$$.....but what setting on the FX3 are you using?

I ask because on setting 3 ( performance? ) setting my rear view along with the side mirrors are useless after about 130. This used to happen in the #2 ( sport? ) setting with the original shocks, and at #3 my eyeballs were vibrating. Okay the roads are proly better where you are....but just saying that the firmer the FX3 setting the more and sooner my mirrors bounce into uselessness.

The only thing with my experience is that I don't hear anything, it's just the chassis transmitting the road conditions, mostly bad, thru the rest of the car. It's enough to make you want to slow down.


Tom

I have a few cars in my inventory as a test bed. I checked on a few roads some as new as 6 months and as smooth as a babies butt. One of my other rides has the same tires, smooth well past 130...It's the car for sure.

Settings either in the middle or the perf setting.

AND I will add I appreciate ANY and all assistance. You guys on this forum are awesome and I thank you for it.

[rhipsher]

Is the vibration coming from the rear. In other words if you reach behind you and put your hand on the rear where your two little compartments are can you feel it or is it coming through the sterring wheel?