Hi all..

I hope someone can help me figure this one out.. as I hope and pray it isn't what I think it is lol..

Anyway.. if I start to drive my car and get on the peddle a little hard when starting out.. I get this awful "CLUNK" and feels like I ran over a boulder.. otherwise.. it is fine..

I didn't start having this problem until a few days ago.. but, it is kinda embarrassing..

I have the 305 tbi with 4 speed tranny in a 89 Camaro RS

Thanks in advance

 

Sounds like the trans mount is toast.

JamesC

 

Same thing happened to me- it only gives a loud, noticeable clunk on a hard acceleration. Slow accelerations don't do it as much, and everything is fine while just driving around right? If so, it is most likely the transmission mount (that's what my mechanics told me)- this thick block of rubber on a metal backing that holds the transmission still against the cross member (I think). Without it, the transmission beats against the chassis. It was fairly cheap to have it replaced, and you can always upgrade to a polygraphite unit for greater durability (but I would guess a stiffer ride to some degree).

 

Just get a poly mount. You wont regret it.

 

Jacking the car up will require more time than replacing the mount. Only basic handtools are needed.

https://www.thirdgen.org/trannymount

JamesC

 

It probably is just the tranny mount but a buddy of mine's car had a nasty THUNK under acceleration and it was because someone decided to use a standard bolt for the torque arm mount (which takes a fine bitch 10mm on a T5, I think) and it had backed out and the torque arm was bashing in floor.

 

Thanks all for the info.. I will try that Let you know when I get it installed. (Crosses fingers, toes, arms, legs, eyes...)

 

Pray it's a tranny mount and it's not a torque arm bushing.

Maliciously, a bad torque arm bushing carries the same symptoms as a bad transmission mount.

Anyway I spent an afternoon of hell fitting the horribly designed transmission mount into it's "housing". I resulted to cutting about a quarter of the back of the mount off in order to fit it in the housing. It was ridiculous, the single most difficult thing I've ever repaired on a car. Crap was falling in my eyes and stuff down there from the driveshaft and whatnot, it was horrible.

 

What was so hard about it? It's pretty easy as long as you unbolt the crossmember and you lower the transmission so you have room to work.

I've never replaced the bushing, but I've changed the mounts around a few times and I never hadm uch trouble with it. Worst time was when I got my T56 put in and couldnt figure out how it went on there for a coupleo f minutes, and finally realized that apparently the auto TA mounts are different than the manual TA mounts. heh.

 

Well the mount is just not sized correctly. It's too big for the housing. It's impossible to fit it in the housing without modifying either the mount or the housing, and I figured I'd modify the mount.

Also, it was very difficult to "slide" the mount onto the torque arm, the lips are just too tight to fit around the torque arm, no pun intended, also, the torque arm has a natural upward pull to it, so you have to hold that down to where you can slide the mount on, I had to rig up a little block of wood between the driveshaft and the torque arm to force it downward, I literally had to pull as hard as I could to slide the mount on the torque arm, and I'm not a small guy, 6'2 205.

And like I said, that was only half the battle, then you had to figure out how to get it to stay in the housing.

After you somehow get it in the housing and you begin to tighten the bolt for the housing you have to use a combination wrench, those ratcheting box end wrenches worked great, because there's no room for a ratchet.


And transmission mounts are a piece of cake, Like james said before, it takes longer to jack the car up then it does to replace the mount.