My tranny always clunks/lurches when I put it in drive or reverse from a stop, and when it downshifts to 1st before I make a complete stop. But today from a stoplight I gave it gas and it felt like the tranny kicked up very hard and it made my coffee cup bounce out of the cupholder.

Is this most likely the mount? I want to get an OEM one but the dealer wants $60 for it, and the Energy Suspension mount is $25 but I've seen bad things about it in this thread.

What do you guys think?

 

That definetly sounds like your mount, i went with the ES mount and had cray vibration so what I did was remove the plate that comes with the mount that goes between the trans and the mount and I also shimmed my trans crossmember with some 1/8" pices of metal and now voila!!! no more crazy vibrations!! so if were you I would get the es mount but do the first time what I had to do the second time!lol and you will be fine.

if you want more details on what to do just pm me.

 

Buy a new GM HD mount. All of the LS1 applications use the 1LE style. So just ask for one for 98+

 

Thanks guys, I think I'll go with the OEM mount if I can find a good price. If I can't all try 94ZPower's idea.