I have an Energy Suspension trans mount on my IROC. It is a 305 5 speed.
This mount has a shim between the mount and the trans, did this shim come with the mount or is it something from Chevrolet? I think it came with the mount but I not sure.

If the shim came from the Energy mount what is its purpose?

The mount is also toasted.

Mike

 

The flat metal plate that ES provides is only for use on their mount. Its there to pre-load the mount. Only used on the ES mount, not the OEM style. And do put it on.

 

Thanks for the quick reply. This mount only has one bolt going through the cross member, is this correct or should there be two to through the cross member?

Mike

 

I've found some broken bellhousings on 700r4's probably because the aftermarket mount is too stiff and doesn't flex with the stock rubber motor mounts. Also when the shim is used on a housing where the threads are not so good it will finish stripping them when you try to compress the shim. Just some stuff to think about. Sometimes stock is o.k..

 

Every V8 Camaro I've owned had a 700R-4 in it, usually with a 350, and mods, and I've yet to have any problems with the ES mount.

 

Two holding the mount to the trans, one through the cross member. I'm using the ES with shim in my 85 IROC with no problems.

The following cars, according to my CD, were factory equipped with the shim(s) p/n1254001:

82-86 2.5L L4 (LQ9/2.5-2)
82-86 LB8/LB9/LG4
87-89 LB8

The following cars weren't so equipped:

87 LG4/LB9/L98
87-91 LB9/L98
88-91 L03
90-91 3.1 V6 (LHO/3.1T)

The shim(s) or lack of it may be the reason some members complain of vibration issues.

JamesC

 

X2..Ive had an ES tranny mount with good stock replacement motor mounts for many many years. No problems and im sure my 355 has plenty of torque.

ES provides 3 holes in their mount for multiple applications. Using just the center one as the F-body crossmember allows is just fine. I ran mine that way for years until just recently.
I installed a Spohn driveshaft loop which has the 2 outter holes in it as well. I decided to drill the 2 extra holes in my stock crosmember and utilize the outter 2 threaded holes in the ES mount. I figured with the crossmember sandwiched between the ES mount and Spohn DSL, it made for a more secure mounting with the 2 outter holes utilized.

Another thing, you may have to ream out the slot in the crossmember where the bolt goes thru to the mount. The ES bolt that comes with the mount is a little larger than the stock GM bolt I found on my application.