Driveline vibration HELP!

[Redbeard11]

So I have a vibration in my car that starts about 80 mph and gets worse as speeds increase, even if I put in neutral. At about 140 mph today the abs/tc/stabilitrak light come on. Took it home and put it on stands to check under it. Nothing! Went to go put new tires on and lights were off. With new tires same thing! Below 80 smooth as glass. Anybody had this occur to them? Any input is appreciated! Jason

[hou30guy]

Either trans mount or carrier bearing or both. I had to do mines. Dealership trans mount 28 and carrier bearing is 75. Both about 1.5 to 2hrs and very easy

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[Moto-Mojo]

Could be balance. Could be the center bearing, as mentioned. Could be the center u-joint. Could be loose flex disk hardware. That used to be a known issue. It could even be a balance issue with a clutch or torque converter. Though more rare. Vibrations can be tough to find. How many miles on it?

Not every driveline shop has the proper fixtures to balance a Camaro shaft WITH the flex disks installed. Ask them before you take it there.

[hou30guy]

Jack that car up and get in tune with ur car lol, push up and down on that driveshaft close to the trans snout, if u got play then trans mount gone. Go father down on the drive shaft where the heat shield at and do the same if the moves freely too get that carrier bearing. But if u change the trans mount then 9 out of 10 ten it took out the bearing too so replace both

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[hou30guy]

Bearing is kinda pressed on but not really, i used a hammer and small pry bar on the inner lip of bearing center and like 3 hits not hard it came right off and same for putting new one on. Mark the drive line before u pull the 2 pieces apart

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[hou30guy]

I didnt have to move none of the exhaust system, just something under the trans pan and remove the trans mount and support and un bolt drive shaft from the rubber coupler on both ends and slide it out from the front

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[hou30guy]

I did mines a week ago so if u need help i can give u my number and walk u thru it free of course, free technician at ya service, save ya labor coins lol

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[Redbeard11]

So I just swapped out the transmission using new mount and a new one piece driveshaft. I’ve checked the exhaust to see if it’s against the body. What I don’t understand is how it only does it at 80+ mph. Drop below that and it goes away. Gonna have the tires rf balanced and see what that does. At this point I’m guessing.

[Moto36]

My driveshaft bolts at diff came loose and had a weird vibration.might be something to check

[Moto-Mojo]

Originally Posted by Redbeard11

So I just swapped out the transmission using new mount and a new one piece driveshaft. I’ve checked the exhaust to see if it’s against the body. What I don’t understand is how it only does it at 80+ mph. Drop below that and it goes away. Gonna have the tires rf balanced and see what that does. At this point I’m guessing.

Driveshaft imbalance and tire imbalance are VERY different. Think about the frequency at which things are turning. ROUGHLY speaking, a 20" set of Camaro tires and wheels are rotating at 850 RPM at 80MPH. A driveline is spinning at near engine speed. (depending on gear ratios, tire size, etc.) Somewhere near 2500 rpm if 1:1.* At that freq, a driveline is felt (and sometimes heard) as more of a hum or rumble in the floor. The tire freq on the other hand is much slower and generally felt in the steering wheel but can travel around a bit.

This can sometimes help to keep from chasing the wrong thing.

*Remember too that if you maintain the same road speed, going from a 1:1 direct gear to overdrive doesn't change the driveline RPM. The engine RPM changes.

[frankwjr]

rofl...try give'n us the info first...where is the drive shaft from? new? can try disconnecting and rotating the driveshaft 180...but seriously sounds like the drive shaft has lost it's balance....look for any missing balance pads....also were the tires "road force" balanced? I had 1 tire/rim replaced a while back for an accident repair and the body shop just used a regular balancer...over 60 I thought the tire was gonna bounce off...lol...had them redo it at a shop with road force....prob gone...

god luck OP and just a suggestion...until this gets fixed may wanna limit that top speed....just sayin....peace out...

[Redbeard11]

So I originally had a dss 1 piece with a factory m6. On that setup had the vibration. Replaced with a new 4l80e and a new steel 1 piece driveshaft. Same thing occurs with the new set up. At 140 the abs/tc/ stabilitrak lights come on. When you park it and start it back, lights r gone. Just put 2 continental 315/35/20 out back and still same thing. Vibration is definitely speed sensitive and progressively gets worse as speeds increase, but drops out at 79mph. Shifter doesn’t vibrate or steering wheel but in the body and blurs the rear view mirror. Dang if I know!

[frankwjr]

crap! my bad..just realized you put in a ZL1 rear...was this a used cradle or just the components? sumbody else posted and I think it was a similar issue..has the rear cradle alignment been check? all the bolts tight? what kind of cradle bushings? what was the mileage on the rear? and how many have you put it and how hard/often do you hit it? just brain stormin....

[Redbeard11]

Just had an alignment done last week after the new tires. Not sure on the mileage when I got it but I have put about 10k on it. U said somebody posted something similar? What were they talking about?