Okay, I went to install the tranny mount. I found that mine wasn't broke, but it was not bolted to the tranny at all, just to the cross member. So I went ahead and put the New energy suspension one on it, and that definitely took care of the hesitation, and the popping sound when I first hit the gas. But now when I take off, I surely have allot more power, but there is a vibration. (pretty bad) What can I do now? I assume it's the drive shaft and the tranny out of balance somehow. So did I do something wrong? Also is there a way to set this myself where it will be in ballance, or do I need to take it to a shop? Thanks for the help so far guys, you have been dead nuts on with every problem. Thanks in advance!

 

The vibration could be almost anything in the drive train. What has probably happened is since the tranny mount wasn't bolted to the tranny, the vibrationsweren't transfered to the body of the car through the mount so you didn't feel them as much.

Are the vibrations speed specific? Like they start at 75 every time? If so that isa more then likely the driveshaft.

Other vibrations could come from an out of balance engine (crank, flexplate, or worn harmonic damper).

Did you replace the tranny mount with an energy suspension piece? The Polyurathane mounts tend to increase road noise and vibrations compared to rubber mounts, so it could be that it's just more pronounced more.

HTH,

Jim

 

Jim, I don't know about that claim about increased vibration. I never noticed any extra vibration with my poly mount. I do believe there would be extra vibrations, just not enough to FEEL in our hard-riding, loud-exhausted f-bodies with rattling interior pieces.

 

i know some people take the pre-load plate that comes with the es mount, because the es mount is taller than stock.

what i did on mine was use a washer between the x-member and the tranny tunel, it may be ghetto, but it works.

 

Dewey,
When you say "trans tunnel" is that where the crossmember bolts to the frame?

 

yes that is what i am talking about.

i did it that way, because i didn't want to leave the preload plate off, but i did have a vibration at high RPM/speeds. so that moved it down just enough to be tolerable, it still vibrates , but not nearly as bad.

i have been running like that for about a year now, and had no problems (well at least not related to that, i do drive a thirdgen )

 

That may b true if you are only replacing a couple bushings with poly's but I did my whole suspension and it is VERY rough now.

Jim