I installed the SS TC front and rear trans mounts the other day, and after starting the car up it feels like a complete pos. Nothing but harsh virations at idle. I installed the mounts exactly like many of the how to articles describe. After having the trans and engine supported, I loosened the three bolts on the top engine mount, the proceeded replacing the rear then the front. I left the front and rear trans mount through bolts loose so that they could be torqued in sequence. Before torquing, I tried moving the engine around to see it it was going to settle, but nothing. I tightened the back mount bolt, the front, then the top three. So why am I still getting vibrations?

Should I loosen the top motor mount slightly with it being unsupported and try to reallign things?

 

ss tc mounts are not rotated, the motor has probably shifted towards the passenger side. need to re balance with motor supported in place.

 

That may be the case then since I did take the jack out supporting the engine for a moment to get things situated for the front mount. I will give that try, loosen the trans and torq axis mount, and see how it goes. Hopefully that takes care of it without having to reallign all of the mounts

 

subd for results!

I have battled with it for months and went back to stock in the end

 

Did you loosen the 3 upper engine mount bolts, and re-torque to spec?

https://www.cobaltss.net/forums/driv...el-hop-211475/

 

"ss tc mounts are not rotated, the motor has probably shifted towards the passenger side. need to re balance with motor supported in place."

id try this

 

With TC mounts also? Even though it vibrated like crazy, I could still tell that they got rid of the slop feel from the stock LSJ mounts. No way can I go back now. I will make them work, its just a matter of getting everything alligned

Yep, after everything was supported the first thing I did was loosen the top three bolts. Installed the rear mount first then the front, torqued the through bolts to 74 ft lbs per FSM specifications, and then torqued the top three bolts last to 37 ft lbs.

I am going to try what Powell suggested this weekend, and update with the results

 

I know when i installed my mounts i tighted down my tranny mounts but lef my motor mout loose and took the car for a drive, nothing crazy just normal driving up and down the road to let the motor settle and then tightened them down and i had no problems

 

Yes with TC mounts. I loved the way it drives especially in first gear but I just couldn't get rid of the vibration..

 

That's odd....

I used to run straight GMPP mounts & an Ingalls.

When I first installed them I had wheel hop like crazy. I made a thread about it, and learned about loosening the 3 upper engine mount bolts. The weel hop went away, and I was a happy camper.

I then upgraded to a powel rotated stage 1 mount with a GMPP mount in the rear.

I do agree with Vander Nars though.... you should take the car for a spin, and loosen the bolts again just to help align the mounts better. I did that on both of my installs.

 

I spent around 4 hours this evening trying all kinds of combinations to attempt to get rid of the vibrations at idle. I first tried Powells suggestion of realligning by supporting the engine. So first step support the engine, loosen the top 3 bolts a couple turns, loosen the front, loosen the rear, shake the hell out of the engine, retorque the rear mount, then the front, then the top. No luck there. Still vibrates like crazy at idle like the car has POS poly mounts installed.

I then repeated the same process, and jacked the engine up more so from the passenger side to make sure it moved back into place. Still, POS vibes

Next attempt, supported the trans, left the top 3 bolts alone, loosened and tightend the trans bolts, then loosened and torqued the top 3 bolts. Same as before.

At this point I was pretty pissed, trying every jack supporting, loosening, and tightening sequnce I could think of. I finally loosened the top 3 bolts almost all the way out during one of the attempts. I must have been able to move things over some towards the passenger side, since I can bolts markings from before on the engine to top mount brace are more towards the drivers side now.


I have no idea what else to do. I followed these instructions to the tee, including the torque specifications, and loosened the 3 bolts on the top mount as suggested
http://www.crateenginedepot.com/pdfs/19211782.pdf

It not like these are poly mounts or any other aftermarket mounts, they are freaking OEM SS TC trans mounts. I have replaced mounts in many other cars before, never had trouble like this. This should be a simple swap with no tinkering or break in period to make them work. They don't vibrate from the factory in the TCs, and they shoudn't in my car. I am open to trying anything else as I am out of ideas, any suggestions?


I may just have to give this a try tomorrow. How loose did you leave the 3 bolts on the top mount? A couple full turns, more than that, etc?

Was this with the TC mounts? You don't have the slightest of vibrations at all? I hope this works, I want to use these mounts, but I am not going to put up with the vibes

 

it was like 2 turns max, just enough to loosen it then just drive it for like 4 mins, and i have ottp front trans mount and tc rear trans mount, iv got no vibs.

 

Tried it, and it worked perfectly. Thanks Took the car out for a good cruise, AC on, and no vibrations at all. I guess my car had to move around some to setlle the top mount into place, becuase loosening them like everyone says did not work

 

Ur welcome, glad i was able to help out.