Auto Transmission

[rhinton]

I was reading this from FormulaLT1 and just wondering about my own transmission issues.

"Also the Corvette Servo deliver's a faster firmer 1-2 Shift. and The pre-96 4L60-e tranny's in F-body's didn't controll the point when you torque converter lock's up with Flywheel usually around 35 MPH and the cars with the perform button used this style 4L60-e tranny."

Okay, here is my issue (isn't there always something?).
On my 96 Trans Am, which is an auto, I got the transmission rebuilt about 1 month and a half ago. I thought everything was fine and they actually said they upgraded all the parts to the new ones that are out there. Whatever they are talking about I have no idea, when it comes to tranny I know nothing. They also said they are bullet proof? WTF? I just want to know if it won't break for 100,000 miles or so.

The main issue I'm getting to is the shifting. When I'm cruising down the road...sometimes I can tap the gas and hear a slight knock. Don't know whether its the trans or the suspension or a mount.

Now, another is when I'm coming to a stop and it shifts back down to first, I hear a thump sound. I solid thump. Once again I'm not sure if its a mount or suspension or tranny.

Before this was rebuilt they were telling me they had to replace the convertor because it was locking up. Could this be the noise? If they rebuilt it...I would hope that the issue was resolved. Could it be a trans mount? Or could it be my differental? Of course the differental was resealed and looked at before the tranny was rebuilt and everything was okay.
Also it was making the same noise before it was rebuilt.

Any clues would help. I think I'm going to wait for some ideas then head back to the tranny people who worked on it.

[CreepingDeath94]

It sounds like it is probably a tranny mount as it happens when you shift down or up. If the mount is bad, the tranny actually hits the underside of the body making this terrible thud sound. Id look into that first as it really easy and cheap to fix.

[FormulaLT1]

No creeping is right, It sounds like a Tranny mount and I didn't really explain myself in that post you got my quote. Reading that it sounds like I'm saying that the flywheel and torque converter aren't normally attached which isn't the case. Lock-up normally takes place without any sign what so ever and all PCM data must be met for it to happen your pcm would set a code if torque converter lock up wasn't taking place when it was suppose to and your check engine light would be triggered.

[KaotiKCamaro5]

it does sound like a tranny mount.. speaking of that.. mine's been broken for about a month because i just got the part.. i gotta get it done before this weekend..

[hotrod_chevyz]

Shift kitted transmisions chew up tranny mounts,especially with a good motor.If its fresh as you say it is,you would think they would replace the mount with a brand new one.If they put a cheap enough mount in it to fail this rapidly,it leaves the question,is the transmission upgrades they spoke of really just some cheap aftermarket get me by remedy.Check all of your 4 link bushings,and your u-joint too.Or just take it back and complain.

[rhinton]

Thanks guys.

I'm going to take it back and complain about it. Hopefully they will be open on Friday, guess I need to call.

I asked them about my mount before they started working on it. I think I said something like, "I've been hearing a thump sound behind me and kinda feeling it as I drop down into 1st, is that the mount?"

"No, its good, its your transmission thats messed up."

Ugh, okay.
I wish I knew more about them, looks like I need to educate myself in the trans. I wish I could have just swapped it for a manual. Would be more fun.
Sucks when its your daily driver.

[rhinton]

Originally Posted by KaotiKCamaro5

it does sound like a tranny mount.. speaking of that.. mine's been broken for about a month because i just got the part.. i gotta get it done before this weekend..

If yours is broken...then do you hear an unual noise whenever your car is downshifting?

[KaotiKCamaro5]

not that i notice.. but my car does make kindof a thump when i accelerate.. i know its the tranny mount because it's happened before.. right when i got the car it was broken.. so i had it replaces.. they just went with the OEM because it was cheaper.. and they said it would hold up ok.. but when they installed the shift kit they didnt change the mount.. so when i raced my buddy's firebird, there went the mount again.. so this time i got a nice polyurethane mount thats supposed to hold up ALOT better.. they have em at LMPerformance.com

http://www.lmperformance.com/4289/2.html

[hotrod_chevyz]

My *thumping* noise was coming from the torque arm bushing.Mine started making a noise when i would goose it,and when i first put it into gear.After looking at how flimsy the torque mount was designed,i built my own custom non-rubber mount.The new one Mounts to the four back tail housing bolts themselves,instead of the two horizontally placed holes the factory mount uses.I will post pictures of it in my gallery if i can find them.

[rhinton]

Originally Posted by hotrod_chevyz

I will post pictures of it in my gallery if i can find them.

Awesome, I'll take a look at that too.
I thought about buying a polyurethane mount a while ago, so I guess I'll give that a try too.

[DarkblueTA]

Originally Posted by hotrod_chevyz

My *thumping* noise was coming from the torque arm bushing.Mine started making a noise when i would goose it,and when i first put it into gear.After looking at how flimsy the torque mount was designed,i built my own custom non-rubber mount.The new one Mounts to the four back tail housing bolts themselves,instead of the two horizontally placed holes the factory mount uses.I will post pictures of it in my gallery if i can find them.

I have my tranny and torque arm bushings as poly's. A little vibration at first....................ok ok ok....a lot but after a thousand miles or so, it was good to go.

Of course, I have a stage 4i Spec clutch(one manly anti-theft device ), 6 speed and I'm not exactly stock.

[hotrod_chevyz]

thats cool.i have solid steel non rubberized engine mounts,and transmission torque arm mount.i kept breaking them,and wanted to move on to bigger and better things,so i made a permanent remedy to my situation.sure its shakes cause the fat daddy cam,but i dont care about the shaking,i can trust they will never break again.(i hope).my air cleaner sits so close to the hood,that if i break a mount,it could ruin the air cleaner or hood.

[CreepingDeath94]

You guys need to be carefull when putting these unbreakable mounts in there as when something breaks its not going to be a cheap easy mount but whatever is next weakest down the line. If the tranny mount is solid, maybe the U-joint will snap instead if the torque is enough...just saying.

[hotrod_chevyz]

yeah thats true,definatly somthing to think about.unfortunatly some of us have clearance issues.the last engine mount i had break on me destroyed my hood.my air cleaner up and hit the hood on me,and caused a reverse dent,right in the middle.I had to hunt up a new tail housing for my transmission,because when i jumped some rail road tracks,it broke the tail housing clean in two .so i decided to move the location where the torque arm mount bolts to.now instead of using the two bolt holes built into the tail housing,i use the four bolts that actually hold the tail housing to the transmission.

[DarkblueTA]

Originally Posted by hotrod_chevyz

yeah thats true,definatly somthing to think about.unfortunatly some of us have clearance issues.the last engine mount i had break on me destroyed my hood.my air cleaner up and hit the hood on me,and caused a reverse dent,right in the middle.I had to hunt up a new tail housing for my transmission,because when i jumped some rail road tracks,it broke the tail housing clean in two .so i decided to move the location where the torque arm mount bolts to.now instead of using the two bolt holes built into the tail housing,i use the four bolts that actually hold the tail housing to the transmission.

Now now...no Knight Rider action in your car....unlike KIT, you'll break stuff. (would have loved to see that jump though)

I agree with you. Sooner or later, I'll get an aftermarket torque arm, but it will be mounted not on the tranny, but the bolt holes in the floorboard. I believe its sphon(sp?) that makes one like that. I don't like the stess being put on the backend of the T56.