I've owned my 1998 Z28 Camaro since early 1999(8K) miles (almost 19 years) and while it was still under warranty .

Posts about loose pinion bearings and a clunking rear end were in the hundreds back then when these cars had less than 36k. Ask me how I know? Because GM techs admit the 10 bolt should never have been installed in these cars because the rear ends where built so cheaply.

So the typical response to the customer when you took the car in was that they all sound that way and send you out the door up until the car would go out of warranty. After warranty, GM was more than happy to replace them.

Same for the aluminum driveshaft that had internal welding cracks and it would tick and ping when you put the car in gear. Same reply, they all sound that way. BTW - they finally did replace the driveshaft under warranty because the weld was visible externally. And of course - elcheapo front rotors that would warp too -same GM reply

As for my second reply in this thread, I thought the OP should rule out the easy stuff first then move on to the rearend. My statement "If it still continues to vibrate, then perhaps the pinion bearings are bad." is actually in agreement with you. Sorry that you didn't read it that way.

The OP's mechanic said the bearings were 'loose'. If he did suggest to the OP that they should be replaced - the OP doesn't say. Should the mechanic instead have told the OP that the bearings were 'bad' and should be replaced? IMO - if that was his diagnosis - that's exactly what the mechanic should have suggested. "Loose' IMO isn't best word to use if something is worn out and needs to be replaced.

For you, 'loose' means the same as 'bad and should be replaced'.

To me 'loose' means there is some play. Back in the day just loose wouldn't get them replaced.

On a side note; it is suprising that no one has asked the OP how many miles are on the car.[/QUOTE]

It wasnt my mechanic that noticed it but the person who rebuilt my trans. He noticed a small bit of play when you would move it by hand but not a lot. He recommended me that its the bearings or pinion yoke that would need replacing. as for the mileage on the vehicle, My 6.0 has 91k while the car has 165k. Maybe it is time to replace those bearings.

 

It is rare for a 4L60E to cause a vibration, and when it does it does so constantly, not during shifts. Like Jay (in post #5) others have reported vibration in 3rd gear due to installing "The Beast" sunshell, many of which are poorly made and out of balance. Hence I always suggest the Sonnax sunshell or even just a newer OEM one.

As everyone is suggesting, either the pinion bearing in your rearend and/or poor driveshaft angle is causing your vibration. And the poly trans mounts are greatly amplifying the vibration. I also suggest going back to OEM trans mounts, but even if that by itself seems to solve the problem, you should find and fix the source of the vibration before it gets worse.

 

Youre right. The Poly Trans mount is amplifying the vibration. You can feel it all in the center console. Im stopping by at the mechanics on thursday. Will report back. Thank you all for your replies.

 

Hey guys good morning.
I just got back from my mechanic. He took the car for a drive and he felt the that vibration. Lifted it up on jack stands to check out the driveshaft, U-joints and Pinion and it look fine. No Pinion play either. He said its definitely transmission. So at this point, What can I do? I just messaged my Trans guy to see what can he do. My mechanic said he left the car well, shifts amazing, just with a vibration.

 

I've read almost every 4L60E thread on this forum for the past 5 years, posted 6000+ times and in none of those has a driveline vibration ever been caused by the transmission. (With the exception of the occasional vibration in 3rd gear). Guess this could be the first one, but I would first suspect the converter or flexplate as both of these were "touched" when the trans was re-installed.
Were either the converter or flexplate replaced?
Who installed the trans?
If you, what was the gap between the converter pads and the flexplate?

If the trans rebuilder re-installed the trans, perhaps it is time to take it back to them.

 

I have as well or at least the ones that have somewhat the common problem but still no solution. as for the flexplate being touch, I have no clue. I would have to ask him when I see him again this upcoming week. We are gonna put it on a lift, remove the driveshaft and see if it does that same vibration. If it does, then that will tell me that it is the trans. I would have to have him look into the flexplate if possible. So the first time he gave me the car, the vibration was there, stock mounts, would come and go. its weird. I return the car again to him and he replaced the 3-4 clutches and the TC. He gave it back to me and it responded better but the issue was still there. I noticed the other day that the same vibration, you feel it when you rev it as well.

Honestly, after I see him, Im considering taking it to a driveshaft place for balancing and new U joints. I may just wait out and see if I can find another Trans locally, maybe even built for cheap but thats my option at the moment. Since my motor is a 6.0, lets say hypothetically speaking it was the flexplate, Do I buy a flexplate for the LS1 or LQ4?

 

No tune. Just straight up swapped. My LS1 spun a bearing and I was on a budget, came across a great deal on an LQ4 off a 06 2500HD. Ran amazing till I did a burnout one hot summer day in LA, that killed my trans but before that, No vibration.

 

By the way... I wanna say thank you to those who took the time to reply. Really means alot to me for I have zero knowledge when it comes to big deals like these. I thank you and I hope you all have a Happy New Years.

 

What do you mean by you feel it when you rev it as well? Do you mean that you rev the engine in park or natural and still had the vibration? If that is the case there is no way it could be the drive shaft. Most likely flywheel or torque convertor. Possibly input drum but I doubt it.

 

I was thinking engine misfire also. Waiting on op to answer questions.

 

Hey guys. sorry I forgot about this but yea... the vibration feels slightly when I rev it a little above 2000rpms. The check engine light is due to low efficiency on bank 2.

 

So after much investigation. I messaged RPM Transmissions, asked a few questions and sure enough they said its an out of balance TC.
What are good brands for a stock Torque Converter?

 

 

Only experience I have had in my 98 Z Procharged Camaro is Precision Industries (Vigilante) and Yank (PY 3400). The Vig was way too loose (a 3600). I had it restalled back to 3000 and it was still loose.

So far no trouble with the Yank. I had to have a new hub installed because of a pump failure in the transmission which took out the hub on the converter. No fault of Yank.

Yank replaced hub. Excellent service. Dave said it was still perfect inside. Got it it 2007.

IMO if you do replace the converter don't go too high. My Yank PY 3400 drives almost like stock until you mash the go fast pedal. IMO it's no fun driving in the city with a very loose stall.

Make sure to inspect your flex plate closely before installing a new converter. It might be cracked.

If your converter is bad with trash inside, that means probably that trash has found its way into the transmission and cooler if you have one.

 

Is FTI the redheaded stepchild of converters? I have a billet 3200 single disc in mine and it's perfect. Just wondering why no one seems to use them. Maybe it's because they don't give out stickers

 

Op ask about a stock replacement converter, not a high stall one.

 

Evidently I did. The very next poster provided the information the op was looking for. Thank you.

 

Hey guys. Thanks for really taking the time in helping me out. Really means alot. The thought of a higher stall never really came across my mind. I dont race the car. Its just my daily but I wouldnt be oppose to hearing suggestions on brands.

 

I clicked your link but those codes didnt pop up on the list.
So I searched it on google and this popped. Is this the one?

 

There should be a sticker on your stock converter, flex plate side, with the correct code for your car. Call Transtar and give them that code and they will hook you up. Transtar is a good company to do business with. I use them on most of my builds. If going with a higher stall converter I would recommend a SS3200 Yank.