so i have a gt car, a 90 model, with a pretty stout motor and tranny and rearend. i bought some solid motor mounts for it but havent installed them yet. what are the consequences of running solid motor mounts and a regular tranny mount? i can change both but im ready to put the motor ones in now and i have to wait on the tranny mount if needed

 

Some MANUFACTURERS (not internet "experts") say you shouldn't mix solid/poly mounts, and some say you MUST use a poly mount on the tranny if you use solid motor mounts. That tells me you're okay to mix them if you want.

Fwiw, I'm using UPR solid motor mounts on the engine in my True Street '89 and a solid mount on the tranny.

 

+1^^^ He shoots, he scores!

 

I'd say if anything it would be preferable to have a poly trans mount if you're going with solid engine mounts. Gotta have that vibration dampened somewhere, it surely isn't good for the driveline. That said, I have no experience with solid mounts aside from my physics education.

 

I've been using solid engine mounts with stock type trans mount for 35+ years.
Works fine.
DO NOT EVER,EVER, USE A SOLID TRANS MOUNT WITH THE SOLID ENGINE MOUNTS..........
Seen a few folks bust tranny cases doing this.....

 

I'm running solid motor mounts with factory tranny mount in my car. No real complaints, even with lumpy idle, car doesn't shake/vibrate to bad. Its not my daily driver so I like it. One thing is I can't keep starter bolts in, every 3-4 weeks, need to tighten them up, don't know if that's from the solid motor mounts but that sure gets your attention when the starter drops and meets the flywheel at speed.

 

lol...

 

I'm running solid mounts on both my motor and trans, I have had a few random bolt vibrate loose (never my starter ones) I know that would suck but it doesn't vibrate too bad going down the road and I've been runnign them almost 2 years drag racing it and hasn't harmed anything.