1-2 shift hits limiter with log info
08-13-2008, 04:00 PM
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1-2 shift hits limiter with log info Rebuilt 4L60E in a 2000 Z28 with a Transgo kit and Yank 3600. 1-2 Hits the limiter a few times before the shift. Its driving me crazy. I pulled the trans and the 2-4 band and new drum still looked awsome. Everything inside looks great and all other up shifts and down shifts are great. I build lots of 4L60e trans and never had this problem or I can fix it quick. I have had bigger converters with no problems.
The 1-2 MPH is set at 37
The 1-2 RPM is set at 5800
Revlimiter set at 6700
I have two WOT logs
In the first log the scanner shows that the current gear changed from 1-2 at 6678RPM @ 48MPH and finished the shift at 6778RPM @ 48MPH The 6678RPM is in the frame that the O2 sensor show a drop from hitting the Revlimiter.
In the secound log the scanner shows the current gear change from 1-2 at 5766 @ 39, thats my 5800 shift RPM. The very next frame shows current gear as first not secound and then the car keeps pulling untill 6548 @ 46mph. The shift finishes at 4749 @49 MPH. Again the 1-2 shift happens at the same frame in the log that it hits the limiter.
My 2-3 shifts never hit the limiter but they show a lot of the same. They show the current gear shifting from 2-3 when I want but calculated gear is still 2nd and in the next frame its back in 2nd for current gear. It will then keep climbing in RPM's up to about 6500 and shift just before hitting the limiter.
Basically on the log, looking frame by frame I have a current gear of 1 on and then at the programmed shift time point the next log frame will show 2 and then the next log frame will show 1 again. The whole time the calculated gear is 1 and the car keeps climbing untill it hits the revlimiter. At that same frame as the limiter the car shifts to 2nd and all is well.
I feel nothing weird during any of this and the car shifts great other thean wot 1-2. All MPH are met and I have lowered and raised the limiter with no change. It just keeps reving untill it hits the limiter and then shifts. Around .4 shift times and 240-260 psi pressure.
Any suggestions, that have worked for other people.
The 1-2 MPH is set at 37
The 1-2 RPM is set at 5800
Revlimiter set at 6700
I have two WOT logs
In the first log the scanner shows that the current gear changed from 1-2 at 6678RPM @ 48MPH and finished the shift at 6778RPM @ 48MPH The 6678RPM is in the frame that the O2 sensor show a drop from hitting the Revlimiter.
In the secound log the scanner shows the current gear change from 1-2 at 5766 @ 39, thats my 5800 shift RPM. The very next frame shows current gear as first not secound and then the car keeps pulling untill 6548 @ 46mph. The shift finishes at 4749 @49 MPH. Again the 1-2 shift happens at the same frame in the log that it hits the limiter.
My 2-3 shifts never hit the limiter but they show a lot of the same. They show the current gear shifting from 2-3 when I want but calculated gear is still 2nd and in the next frame its back in 2nd for current gear. It will then keep climbing in RPM's up to about 6500 and shift just before hitting the limiter.
Basically on the log, looking frame by frame I have a current gear of 1 on and then at the programmed shift time point the next log frame will show 2 and then the next log frame will show 1 again. The whole time the calculated gear is 1 and the car keeps climbing untill it hits the revlimiter. At that same frame as the limiter the car shifts to 2nd and all is well.
I feel nothing weird during any of this and the car shifts great other thean wot 1-2. All MPH are met and I have lowered and raised the limiter with no change. It just keeps reving untill it hits the limiter and then shifts. Around .4 shift times and 240-260 psi pressure.
Any suggestions, that have worked for other people.
