Well the other day I regretable was doing donuts at work and the next thing I know the shifter started bouncing up and down on initial take off and right after i let off on 2nd. So now every time I get going after a red or stop sign the actual shifter starts moving up and down like literally 6 inches. So i got underneath this morning and could not find a single thing out of the norm. I drove it woithout the shifter plate and noticed that the whole tranny was moving not just the shifter. Im really scared cause i did see driveshaft marks on the ody and I know those things are really sensative. Anyways i was wondering if anyone can give me some advise or lead me somewhere because Im lost. The crossmember seems fine but the support between the tranny and crossmember seems weak but I have NO idea what to do. Thanks

 

try to pry up at the mount on the tranny and see if it moves that will tell you if your mount is bad

 

ok thanks, i also heard a bad motor mount can cause that, is there any way i can check those, i know their located between the motor and frame but how can you tell if their broke? Thank you

 

well i jacked up the crossmember with a 2x4 between the jack and member to see if the cushing between the 'member and tranny gone bad. I jacked it up and with the driver door open i kepped an eye on the shifter and didnt see any movement. I also watched the shifter as I lowered the jack back down and still didnt see the shifter move at all. So can this be the engine mounts? How can I test to see if any have gone bad?

 

slowly and carefully jack up the engine. or if you have an engine hoist that would be better and do the same thing

 

well i drove the car in my driveway with the hood up and right when i planted 1st and when the tranny will start bouncing i noticed the air cleaner was moving around alot too. So it IS an engine mount. Well the good news is that someone is selling me a 350 .040 over with double chained timing and 202 heads and 455 cam and said he will swap it over to my camaro and said for $100 he would replace the mounts. How does that sound? So for the whole deal (engine, swap, gaskets, mounts) he said he'll do it for $1200. What do you guys think?

 

i think as long as you have the engine out you should change the tranny mount bushing too. they are about $12 for a good one and it will never be easier to replace than when the engine is out. since you said you tried to jack it up from below the crossmember a broken mount wouldn't be visible. try jacking the tranny up from the pan .use several blocks of wood between the jack and pan. each piece should be at least as long as the pan is wide so you don't dent the pan. if the car starts going up too... stop lifting! trannies arent that heavy!

 

it shouldnt cost you 100 bucks to change out the engine mounts,they only cost like 5 bucks do it ur self and save 90 bucks.

 

That sounds like your transmission mount rather than an engine mount. If it were your engine mount then I dont think your tranny would only bounce on acceleration and shifting. if it were the engine mount the car would vibrate all the time. At least that is what I think.

 

i thought of that too, but when i jacked the engine up it did rise further up on one side then the other, but if it is an tranny mount, im effed cause the guy as we speak is finishing up in dropping the 357 in, and if it was all screwed up with the Piece of s#it 305 just imagine, according to the guy, 375 hp doing the pulling. How hard is it to change a tranny mount, is it the rubber piece right between the tranny and crossmember?