auto trans mount bolt size

Reply Subscribe

Thread Tools

Search this Thread

May 22, 2014 | 11:03 PM

at23520

Thread Starter

On The Tree

iTrader: (1)

Joined: May 2006

Posts: 123

Likes: 0

From: a "ville"

auto trans mount bolt size

i just installed a prothane tranny mount on my ta. something i noticed when doing it, it is a little thicker than the stock one. when i got it in completely, it has my trans pushed up at a angle and it makes vibrations now.

what i need to know is what size are the tranny mount bolts so i can get longer ones to shim down my cross member to make it level.

May 23, 2014 | 08:26 AM

mrvedit

Moderator

Joined: Aug 2010

Posts: 7,323

Likes: 529

From: Ann Arbor, MI

Why not just install a stock tranny mount. There are dozens of threads here about members having vibration problems with poly mounts, in each case the problem is solved with a stock mount.

May 23, 2014 | 09:21 AM

at23520

Thread Starter

On The Tree

iTrader: (1)

Joined: May 2006

Posts: 123

Likes: 0

From: a "ville"

Because the prothane is a stronger piece than stock and it was $50 cheaper.

May 23, 2014 | 10:12 AM

redbird555

TECH Veteran

iTrader: (14)

Joined: Mar 2009

Posts: 4,444

Likes: 9

From: Pompano Beach FL

Well if its causing vibrations thats not good. However poly will transmit much more vibration than rubber. When I had mine in for a couple weeks it would consistently rattle any change in the ashtray. There are different heights available but idk the part numbers. Do you have rubber motor mounts still? If so thats a huge no no to having a poly trans mount. You can find the oem style mount anchor 3125 on rock auto for around 40 bucks. I have never seen a case where a good stock mount wasnt enough. I have an m6 which is much harder on the mount than an a4 is. I tried the poly brifely and hated it ordered a new anchor one from rock auto and its been holding fine for 2 years

Last edited by redbird555; May 23, 2014 at 10:48 AM.

May 23, 2014 | 12:03 PM

at23520

Thread Starter

On The Tree

iTrader: (1)

Joined: May 2006

Posts: 123

Likes: 0

From: a "ville"

Yea rubber motor mounts for now. I have a shift kit in the trans now and that busted a stock mount.

I'm calling it a vibration but it feels more of a pinion angle problem due to the alignment of trans now. Feels like it did when I lowered my truck 4/6 and didn't set the pinion correctly.

May 23, 2014 | 01:02 PM

01ssreda4

TECH Senior Member

iTrader: (96)

Joined: Aug 2007

Posts: 24,241

Likes: 89

From: Turnin' Wrenches Infractions: 005

Yes they raise the trans, yes its known to cause vibrations due to the change in driveline angle. No there is nothing you can do except remove it or if its the type that has a thrust plate install it without the thrust plate.