A4 Transmission clunk
Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
A4 Transmission clunk
Hi all.
I have a 97 C5. I bought a stage IV A4 transmission from RPM about a year ago. After we initially installed it. I noticed it shifted very firmly from 1st to 2nd, and firmly but not as bad from 2nd to 3rd. I contaced RPM at the time and asked if that was normal but I guess they couldn't really answer without seeing the car. The transmission has always worked fine, but yesterday, all of a sudden it really makes a clunk shifting from 1st to 2nd....kind of like it was doing but worse. It also seems to have more of a delay when shifting. I'm trying to narrow down the problem. Any ideas on where to start? Could it be line pressure, computer problems, or do you think its something in the transmission? Any help would be appreciated.
BTW I have a 3400 stall converter and use Royal Purple in the trans. I have a trans cooler and temps are always between 140 and 200. I run 3:42's and have a brand new transaxle. I don't race or abuse the car, but I do get on it sometimes and it has always performed well.
In fairness to RPM, I have sent and e-mail to Rodney, but they are closed on Saturday. I don't even know whether or not there' anything wrong with the trans. Like I said, any help would be appreciated.
I have a 97 C5. I bought a stage IV A4 transmission from RPM about a year ago. After we initially installed it. I noticed it shifted very firmly from 1st to 2nd, and firmly but not as bad from 2nd to 3rd. I contaced RPM at the time and asked if that was normal but I guess they couldn't really answer without seeing the car. The transmission has always worked fine, but yesterday, all of a sudden it really makes a clunk shifting from 1st to 2nd....kind of like it was doing but worse. It also seems to have more of a delay when shifting. I'm trying to narrow down the problem. Any ideas on where to start? Could it be line pressure, computer problems, or do you think its something in the transmission? Any help would be appreciated.
BTW I have a 3400 stall converter and use Royal Purple in the trans. I have a trans cooler and temps are always between 140 and 200. I run 3:42's and have a brand new transaxle. I don't race or abuse the car, but I do get on it sometimes and it has always performed well.
In fairness to RPM, I have sent and e-mail to Rodney, but they are closed on Saturday. I don't even know whether or not there' anything wrong with the trans. Like I said, any help would be appreciated.
Le Mans Master
Joined: Aug 2001
Posts: 8,145
Likes: 1
From: Bradenton FLORIDA
Where are you located? The Stage IV should have very firm, crisp shifts that do feel harsh to some, that is to hold extra HP & to give low ET's w/out the lag evident in a stock tranny. Have you had it programmed? Some times a tuner will add line pressure for the same effect, but on a built tranny the valve body has already been modified to give higher line pressure for longer tranny life. Both on top of each other is to much. I would first have it scanned to see where the tune line pressure is set & go from there. I doubt what your describing is a trans problem since that is the goal of a built tranny. If you were near us we could scan it & tell you. Good Luck!
Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
Where are you located? The Stage IV should have very firm, crisp shifts that do feel harsh to some, that is to hold extra HP & to give low ET's w/out the lag evident in a stock tranny. Have you had it programmed? Some times a tuner will add line pressure for the same effect, but on a built tranny the valve body has already been modified to give higher line pressure for longer tranny life. Both on top of each other is to much. I would first have it scanned to see where the tune line pressure is set & go from there. I doubt what your describing is a trans problem since that is the goal of a built tranny. If you were near us we could scan it & tell you. Good Luck!
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
The harder shifting is tougher on the rubber bushings and since you have the earlier designed Torque Tube (10mm vs 12mm bolt).
Since your car is older it may be the bushings as they tend to fall apart as they get older.
Le Mans Master
Joined: Aug 2001
Posts: 8,145
Likes: 1
From: Bradenton FLORIDA
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Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
I guess that would be a logical place to look if it's not the computer or trans.
Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
OK, I have narrowed it down a bit. Took the car out this moring, testing my nitrous wet kit, casual driving, hard driving, no clunk. Came home changed out my 100 shot to a 150 shot and on the way out, it starts shifting hard again. So, if it were the torque bushings, it would have done it every time. I think, I can safely eliminate that.
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
OK, I have narrowed it down a bit. Took the car out this moring, testing my nitrous wet kit, casual driving, hard driving, no clunk. Came home changed out my 100 shot to a 150 shot and on the way out, it starts shifting hard again. So, if it were the torque bushings, it would have done it every time. I think, I can safely eliminate that.
Did you check your rear tranny and motor mountd, to make sure they are tight
Last edited by ajg1915; Aug 13, 2007 at 10:23 AM.
Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
Clunking is the best way I can decribe the way it's shifting. It forcefully shifts hard and sounds like it's banging into gear, but it doesn't do it all the time.
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
When was the last time you changed fluids and what kind are using ? Also have you checked fluid level ?
Thread Starter
Melting Slicks
Joined: Sep 2005
Posts: 2,625
Likes: 1
From: Rhode Island
Topped it off a few months ago when the tranny was installed. Using Royal Purple. OK to use according to RPM. Not low on fluid. Still shifts OK, just firmer than before. Taking it to Dez Racing this week. He also thinks it could be line pressure. He's going to check it out.
Race Director
Joined: Jan 2003
Posts: 19,802
Likes: 0
From: San Antonio Texas
St. Jude Donor '05-'06-'08
Sounds like you are having the same problem I did ! ! In my case, my torque converter broke, locked up the tranny, torque tub and starter! ! I had to get a new starter, rebuilt the torque converter from a 2600 to a 3400 and rebuilt the tranny wich it was time because Rodney built it about 3 years ago ! ! I also added a transbrake ! ! !
Im happy now, it should be running in few days ! !
By the way, my transmission always shift hard from 1 to 2 but when I went to the track, it shifted like an Escalade Transmission! !
Im happy now, it should be running in few days ! !
By the way, my transmission always shift hard from 1 to 2 but when I went to the track, it shifted like an Escalade Transmission! !
Former Vendor
Joined: Apr 2001
Posts: 2,719
Likes: 3
From: Anderson Indiana
First step is to hook up a scan tool (preferebly a Tech II) Check for any codes (some do not command the check engine light) then moniter TCC slip. If everything appears normal at this point I would install a trans pressure guage. I will bet you find the problem with the scan tool and I doubt it will be an internal transmission problem.Feel free to give us a call any time 1-800-406-1109. 
Racer
Joined: Apr 2007
Posts: 380
Likes: 0
From: Long Island New York
Maybe you guys can help me with this tranny problem. I have an 04 A4 with the stock tranny all I have done is a 3.73 rear and ever since I did the rear about every 100 mile it will start to shift hard and when I say hard I mean HARD! I checked for codes and what I got was P0894 I clear the code and the tranny shifts fine for another 100 or so. Any ideas?
Safety Car
Joined: Jul 2005
Posts: 4,275
Likes: 4
From: Vancouver WA
Mine is doing the exact same thing. My tranny wasn't built by RPM, but it's a level 5 tranny, 3000 stall, and 3.42:1 gears. It shifts nice and quick when I first drive it, but after it warms up to full temp, it shifts so hard it sounds like it's about to break the differential.
Safety Car
Joined: Jul 2005
Posts: 4,275
Likes: 4
From: Vancouver WA
First step is to hook up a scan tool (preferebly a Tech II) Check for any codes (some do not command the check engine light) then moniter TCC slip. If everything appears normal at this point I would install a trans pressure guage. I will bet you find the problem with the scan tool and I doubt it will be an internal transmission problem.Feel free to give us a call any time 1-800-406-1109.
Maybe this is why I am seeing my check engine light on now, but the car runs fine.
Former Vendor
Joined: Nov 2005
Posts: 8,995
Likes: 2
From: Spring Texas
St. Jude Donor '08
Mine is doing the exact same thing. My tranny wasn't built by RPM, but it's a level 5 tranny, 3000 stall, and 3.42:1 gears. It shifts nice and quick when I first drive it, but after it warms up to full temp, it shifts so hard it sounds like it's about to break the differential.
