tblu92

You should not have to make a speedo correction on a C6 when doing a gear change--because it's a transaxle and the speedo sensor is on the output on the diff ( not like a Camaro which has the sensor on the trans)
HOWEVER you DO have to make a shift point adjustment to all the upshift/downshift tables as well as all the TCC lock/unlock speeds
When going from a 2.73 to a 3.42 it requires a -25% change
Hard shifts you are getting is that the TCM has gone into a limp mode which makes the line pressure go to the MAX PSI----all the time

PS Check you actual speed with another source like a GPS 1st to see if the speedo is correct---IF so leave all the diff stuff alone and do the shift corrections-----
25% is a HUGE change and no way it will shift correctly until done--- Some limp modes will leave the trans in 2nd gear all the time---

ALSO is your trans stock ? Is your converter stock ??

jim2092

An A4 C6 has to have the gear ratio changed in the tune. But not a manual. You were wrong in 2011 too.

https://www.corvetteforum.com/forums...imiter-a6.html

GhostC6

Do you guys know if my problem will also be solved with a TCM or ECM tune? I have the A4 and had it rebuilt and upgraded and also had the Torque Converter rebuilt and he changed some componets and did some other things like they do in the TCI and other High Performance Converters and he did say he was going to take my information and change my stall to where it would perform best.

Long story short, since the stall is different, and the A4 has been upgraded, I am getting the P0700 code, then it goes to max pressure. I reset the code and I am good for a short time and then the code will come on, then max pressure, reset the code, then back to normal.

I have tried different TCM tunes for normal, firmer and hard shifts. Each one allows me to drive it either a little more or a little less before the code comes on. I don't have the knowledge or ability to change the TCM the way it needs with the tool I have, so that is why I ask if a tuner can solve the problem with a "Real" tune?

Thanks for your help.

jim2092

You have been told by several people that a stall change requires a PROPER tune change. I don't know what else to tell you.

GhostC6

Thanks man, sometimes with all the different comments I get confused so thanks, now I know for sure.

What exactly does the tuner need to adjust, the shift points by RPM or is it something else they need to adjust. I know, any tuner worth paying will know, but I would like to know also rather than saying they know and then them say I adjusted it and it is fixed but I never know what it is.

Thanks again.

jim2092

Things that could/should be changed would include shift points, shift firmness, TCC lock/unlock speeds, TCC modulation and main spark advance.