99mongooSS

iTrader: (4)

yeah I was about to say most guys that ive seen with those mounts have solid motor mouts too. Im gonna try one in my motorplate/powerglide setup im working on.

Engine_HP

iTrader: (1)

its good i read this read i was going to put in a prothane tranny mount for my M6

Lt1Porsche

iTrader: (6)

I can 100% sure say that the mounts were not the cause of those vibrations. Those vibrations are another problem that still exsist. The mount helped him feel the vibrations. So dont frown on the mounts because someone else is having an issue. For every car that has vibration issues with those mounts there are 5 right behind him that have no issues.

nighthawk15

What in the world? My STOCK stereo can cause the mirrors to shake more than any drive line vibration on the freeway. That's not an exaggeration. Stuff doesn't rattle around in my car at all.

3zman

ws666:

Thanks for posting - I just broke my third rubber rear mount and was thinking of putting the prothane back in but you refreshed my memory with respect to what I went through 3 years ago. Granted, I had additional problems - poor alignment, front and rear driveshaft angles, etc.. After I chased those down the final touch was the rubber rear mount. My ride is almost 400/400 at the rear wheels so it's not a supercar, and it is a tricked out 4l60e.

Bottom line - I'm going to buy 2 GM rear mounts; one for today and one for next time.

01ws666

Do you have a torque arm relocation bracket? I'm guessin not if your still ripping them in half... I've read a few posts and it seems to be the best of both worlds.... Use a rubber oem mount for the smooth ride and relocate your torque arm mount to the uni-body so it stops ripping the rubber mounts in half and may also save your tailhousing from cracking some day like mine has before

MY99TAWS6

iTrader: (3)

Well I put various poly mounts on basically new 97ta and my 99 ta m6 and they all had terrible vibrations with the poly mount. Tried leaving out spacer, shaving the humps ,washers..didn't help at all. Cars had horibble vibration and noise. Put factory mounts back on and nice and quiet no vibes.

I thought the auto guys were the ones with no vibs.

I am not sure what going to do with my current build. I also thought the m6 cars broke the mounts more than auto cars. I will think try stock mount for now. They are at least easy to swap out. I am moving my torque arm off the trans as have no choice with the 4l80 swap. It will be on trans crossmember.

01ws666

And like everyone is so kind to point out even though I've Already stated this I do know the prothane mount was not what was causing my vibration There's no way it could have its the exact same size as the rubber mount,I compared them.... However Any little vibration your driveline does have the prothane mount is so stiff it multiplies them to the point some people (me) couldn't drive their cars on the freeway anymore Thanks for the posts and free bumps anyways guys, its good to get more than one point of view on the subject...

xRelapse13

iTrader: (21)

I have prothane poly motor and tranny mounts in my car and there was practically no difference in vibration inside the car. big difference though if you look at engine and how much less it moves around. my car is a true daily driver too, i've put around 16k miles on it in the last 7 months and no complaints.

The Postman

iTrader: (44)

from what i've seen if you do one without the other you run into more vibration than doing all of them at the same time, i have just the tranny mount and it does vibrate...but at least i know its keeping things still under there...i'll be doing motor and torque arm mounts this weekend and hopefully i lose some of the vibration...if its not that then i'll be checking on the driveshaft balancing.

01ws666

Nah I had them all poly motor/trans mounts and poly torque arm bushing. Just ditched the trans mount for rubber and its 100X better.... for me anyways. The rest of them are staying.

crzytown69

iTrader: (17)

i went with all new poly mounts...... im with 011ws666 i ditched mine i couldn't deal with the vibes plus it cracked my tail shaft.... I learned quick that switching from 2:73 to 3:73 with a steel drive shaft and a trans mounted tq arm is not a good combo with the prothane mount.... I now have a aluminum ds and mounting an adj tq arm off the tranny now but i dont have the ***** to try the prothane mount agian i dunno its a combo of a few diffrent things that seem to make these things work like a dream or give you hell....

XtraCajunSS

iTrader: (2)

01ws666,

I would be wary of the torque arm relocation crossmembers in your case... you may end up getting that vibration back. If the vibration is originating in your rear or driveshaft, when you hard mount the torque arm to the body, you will be back at square one... Anytime someone calls me with a vibration problem like you described in your original post, I would ask about poly mounts. I'm sorry you went through so much to figure out your issue, I would have been able to save you alot of heartache...

Thanks,
Shane

3zman

WS666

In answer to your question, I am now using a Spohn torque arm with the relocation arm as you mentioned. What I didn't say was that the rubber mount I just broke was some aftermarket crap made in India (thought I'd save a few bucks - dumb). The other mounts broken were before the torque arm.

nalmak

iTrader: (1)

Damn..I have the have problem as the OP...Dosent help that my rear end is on its last leg..but the vibrations are there at 60-80..Up to 100..And mostly shifting from 2-3..The vibration feels centered in the cabin..but it felt and heard all the way to the rear end..My pinion Angle might be jacked..But shouldnt caue that much of a vibration..

flak_monkey

Wow. You got vibrations out of a poly transmission mount. You get a ******* gold star on your progress report. Have fun replacing the rubber mount every month or two. I went through three in amonth before I switched the whole car to poly mounts.

nalmak

iTrader: (1)

Not polly... prothrane..or whatever..Energy suspension Trans Mount..That's whats causing the Earthquake....I deserve a gold star..**** Monkey

01ws666

lmao @ **** monkey! Thanks for the advice smart ***! I've already addresed what I'm going to do about that issue though

NemeSS

iTrader: (127)

i have prothane mounts all the way around on a m6
vibrates no more than usual, also nver had any negative effects on my previous lt1 car with a4. didnt notice any crazy vibrations at all

XtraCajunSS

iTrader: (2)

Pinion and/or driveline angles can have a profound effect on vibration. There is so much misinformation floating around in this thread. I will state it again, MOUNTS do not cause vibration. Rubber mounts ISOLATE the body from whatever driveline vibrations exist in the car. The only way a mount could contribute to a vibration problem is if they in some way reorient the transmission and change the driveline angles in some way.

Thanks,
Shane