loud "clunk" sound from under car
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 960
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From: Central, FL
loud "clunk" sound from under car When the trans up shifts into 2nd, you hear this loud "clunk" sound, I was thinking it was the trans mount because had the same problem with another f-body in the past and it was the trans mount. well, I got under the car and checked it out... the mount didnt look that great, but it didnt look split or ripped or anything. BUT, while I was under there, I noticed that the bushing for the TA attached to the trans looked split. is it supposed to look split? it looks split straight thru. can that cause that clunking sound??? Please help ASAP. Taking the Trans Am on a 1100 mile trip in 3 weeks. 
PS: 00 Trans Am A4 3.23
stock trans and suspension
PS: 00 Trans Am A4 3.23
stock trans and suspension
Teching In
Joined: Jun 2004
Posts: 35
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From: Hampton VA
Not really going to be much help but, I've had two transmissions rebuild t and both have done this once re-intalled. In the first one we know that the problem was. It was in a beater truck that had a missing tooth in the gears. No biggy. (That was like over 15 years ago and the damn thing is still running around town!!!!!) The other is a TH350 we just did last year on my truck. Everything went ok on the install though. What I'll do is call the transmission place that did the work and ask. I just gotta find the number!
TECH Veteran
Joined: Aug 2002
Posts: 4,055
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From: Hartsdale, NY
Put your hand on the tranny tail shaft and push up as hard as you can; this will usually identify a broken trans mount. Also check the motor mounts...
If this is not a problem, check your driveshaft U-joints by twisting the drive shaft clockwise and counterclockwise while your car is in park. If the needle bearings are worn out in the U-joints you will know it....
These are the most common sources of clunking noises...
If this is not a problem, check your driveshaft U-joints by twisting the drive shaft clockwise and counterclockwise while your car is in park. If the needle bearings are worn out in the U-joints you will know it....
These are the most common sources of clunking noises...
TECH Veteran
Joined: Aug 2002
Posts: 4,055
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From: Hartsdale, NY
i suppose it also could be a few teeth missing in the rear end.... but my guess is that this would not clunk only on a 2-3 shift....
a bad auto tranny will go clunk on a 2-3 shift but the mounts and U-joints are a more likely source to check first..... How does it shift - firm, soft, mushy?? ...and the fluid - is it nice and brown and does it smell like a burning oil refinery?
a bad auto tranny will go clunk on a 2-3 shift but the mounts and U-joints are a more likely source to check first..... How does it shift - firm, soft, mushy?? ...and the fluid - is it nice and brown and does it smell like a burning oil refinery?
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 960
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From: Central, FL
well i figured i would just go ahead and change the trans mount and put in a poly one, and as i suspected the mount was shot.....thats for your imput everyone... woohoo now i get to go on my road trip... 
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12 Second Club
Joined: Nov 2002
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From: MI
I have had both a broken trans mount and a bad U-joint in my '94 (at two different times) and I can tell you that they suprisingly sound quite similar.
BTW - You are going to hate your poly trans mount on your road trip due to all the extra vibration. If your car isn't too built w/ too big of a stall, you can buy an LT4 trans mount. I think it will work with any 4th gen.
BTW - You are going to hate your poly trans mount on your road trip due to all the extra vibration. If your car isn't too built w/ too big of a stall, you can buy an LT4 trans mount. I think it will work with any 4th gen.
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From: SugarLand Texas
Originally Posted by seadoo
When the trans up shifts into 2nd, you hear this loud "clunk" sound, I was thinking it was the trans mount because had the same problem with another f-body in the past and it was the trans mount. well, I got under the car and checked it out... the mount didnt look that great, but it didnt look split or ripped or anything. BUT, while I was under there, I noticed that the bushing for the TA attached to the trans looked split. is it supposed to look split? it looks split straight thru. can that cause that clunking sound??? Please help ASAP. Taking the Trans Am on a 1100 mile trip in 3 weeks.
PS: 00 Trans Am A4 3.23
stock trans and suspension
PS: 00 Trans Am A4 3.23
stock trans and suspension
