2camaros6702

iTrader: (2)

I have searched this and seen a few threads on it but have not seen anyone that has found the problem. I have had a very small vibration in the car sense the day I bought it new. Of course they said they could not feel anything when I took it in many times. I just put a poly tranny mount on the car and OMFG with the car in park and revving it, it vibrates like hell now. I am going to put a new stock tranny mount on it this weekend to see if it will go away some but I would still like to know what it is because it is so bad it CANT be good whatever it is.

Any suggestions?

NAVY99B4C

iTrader: (7)

i have the same issue with my car in park from 1100 to about 1500 it vibrates bad but driving its fine. now i know for a fact my trans mount is bad like tore in 2, but im in the middle of a cam swap so ill just change it now anyway but nobody can tell me what the problem is. if it was the mount it would do it at highway speed since it runs in that rpm range right?

2camaros6702

iTrader: (2)

It's not your mount that is causing the vibration. Mine was ripped in two and I still had the same very little vibration as I did when the car was new but when I installed the poly mount it was real bad. I am putting a new stock mount on it this afternoon so I can drive it. But my question is why is there a vibration that bad in the first place? Just putting a softer mount on it is only hiding the problem IMO. I had a 67 camaro with 637rwhp with all solid mounts and it did NOT vibrate this bad. Someone on here has had to find the problem by now with all the cars with the same problem since 98.

DaveX

I don't know how bad yours is but a cam makes it shake. A poly trans mount is notorious for amplifying whatever undesirable harmonics are there. Poly motor mounts will to a degree, but not as bad as the poly trans mount.

cellulis44

iTrader: (11)

flexplate? converter?

thats all there is in the driveline that is heavy enough to make a significant feeling.

nothing in the trans is really heavy enough to cause a hellacious vibration like you describing.

and honestly are you sure there isnt a misfire?

2camaros6702

iTrader: (2)

I am almost sure it's not a misfire; the car still runs real good. I have broken a flexplate in the past and this is the second converter in the car so I am leaning towards the flex plate again. It vibrates in rhythm kind of like _____--__--_____--__--____--__--____--__--____--__--____--__--____--__--____ the high lines being the vibration. Sorry about the demonstration I rely had no other way to explain it. LOL.

spy2520

iTrader: (3)

wtf is that morse code? lol


i couldnt hold that one back.

2camaros6702

iTrader: (2)

lol!!

cellulis44

iTrader: (11)

holy **** dude my mom is not a *****.. I dont care what navy you learned that in.. that was unaccptable..


sounds like a flexplate.. i guess lmao..

sure you didnt start it twice?

bigboykilroy

iTrader: (48)

its the polly mount.
when you have the stock front engine ones and a polly trans you get bad vibration.
change the engine ones to polly it will be much less, change the trans back to the factory one and the vibration will be gone.

It happened to me as well...but i got good at changing the mounts !!

2camaros6702

iTrader: (2)

A new stock one is going back on today. So it could be that with stock engine mounts and a poly tranny mount it could be creating some sort of harmonics? I could see this being the problem. I am going to get all poly mounts for the engine and install them and the tranny mount together just to test this.

bigboykilroy

iTrader: (48)

Yes Stock engine mounts with a polly trans mount creats unwanted harmonics, the engine mounts allow the engine to flex more than the poly trans mount, the best thing to do is have all 3 the same material all stock or all polly. With the polly you will get more vibration but not as bad as you are getting currently. good luck.

2camaros6702

iTrader: (2)

OK!!!!!!!! I got home and put a new stock mount on the car and it is as smooth as a freshly shaven Wops I was thinking of something else at the moment! The car is good again so the only thing I can think is what was already stated. You must have all the same mounts or it will cause unwanted harmonics. End of story!! WOOOOT

bigboykilroy

iTrader: (48)

AWSOME sooth sailing to you my friend !!

nerisls1z

iTrader: (2)

I had the same problem when i did my a4 to m6 swap you can not have rubber engine mounts with a poly trans mount found out the hard way took trans back all out again for nuthing....

American-Muscle1989

Hi all,

I have this exact problem, the original trans mount was in two pieces and totally broken and was making a vibration under power so I heard the poly mount was a good replacement. Just fitted it and bloody hell, slight rev of the engine in Park and it feels like something is about to fall off, so annoying!!!


2 questions please.

1. Will the vibration go away when driving or will it be there the whole time?
2. If I go back to stock mount then it will smooth it out?

Thanks

G Atsma

You can't use a poly trans mount with rubber engine mounts. Poly engine mounts and rubber trans mount is OK, but not the reverse. You are experiencing the result.

00pooterSS

iTrader: (40)

Poly trans mounts make the interior of the car vibrate like crazy. But it's hard to tell over the internet if you have just the standard vibrations from the poly mount or something else going on. I ran poly ENGINE mounts and had no vibrations, I loved them. I liked them more than OEM mounts. But I always ran a OEM trans mount because the people I knew that had poly trans mounts had a lot of vibration and noise in the car.

Also with rubber engine mounts the engine moves around a lot, and having the engine moving all over with the near solid poly trans mount puts a lot of strain on the transmission case, I've heard of people cracking the trans housing with rubber engine mounts and a poly trans mount. So run all poly, or poly engine mounts with a OEM rubber tran mount. Or all rubber OEM mounts. Do not mount the trans solid (poly or actual solid) and leave rubber mounts on the engine.