i gotta problem w/ my 700R4... when i am at a light and i take it WOT, i get a substanial bump near the rear of the tranny... i have no idea why... what could be the problem.. when i bought the car it was like that... does that mean i need to rebuild my tranny? or just the driveshaft.. i dont know.. but when i get around to putting my 350 in it, i dont want to drive for 3 days and blow the transmission up...

 

Trans mount, like all the rest of these cars...

There's 2 kinds of trans mounts in these cars: broken, and soon to be broken. I guess you could say there's also a 3rd kind: polyurethane.

 

Sounds like a tranny mount. Go down to your local parts sore and get a poly one. Should cost about 25 bucks and install in about an hour. I just changed the one in my LT1. What a differnce. it took me months to figure out what the heck was going on down there. Sounded like the tranny was comming through the console. Do not get a GM unit to replace it with. Some people have gone through 3 or 4 a week they are so bad.

 

Trans mount or loose driveshaft. I also thought it was a trans mount when my brother in law had his like that, it made a loud *** thump when he floored it, almost like a boulder hit back underneath the car. We changed the mount and still had it, he drove home on the highway and is driveshaft fell off. Turned out his yokes were loose.

 

it may sound stupid but i acctually had a problem very similar to that and it turned out to be my Torque arm mount on the tranny

 

ill replace the transmount... if that doesnt work, what do i have to do to tighten the driveshaft???

 

You need to look at the universal joints on the rear of the tranny and see if they are loose. They may not be but that doesn't mean thats they are not bad.

 

hmm.... how do you tell if the are bad?? and if they are, where do I get them?

 

Change your trans mount first. You need one. Worry about U-joints later. They're not causing your trans to thump against the bottom of your car. The trans mount is.

Stay focused on the issue at hand. Don't wander around eveywhere chasing windmills. "The main thing is to keep the main thing the main thing."

 

I thought he didn't know where the noise was coming from? But if is around your tranny than check the mount and the torque arm mount.

 

well it is that the trans jumps... i can feel it... just like i ran over a large boulder but it only seemed to hit near the end of my console.. next time i have it up on jacks, ill replace the transmount with a polyurethane one then ill check back if the problem persists