Harsh 1-2 shift under light throttle after Transgo & Servo install
#1
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Harsh 1-2 shift under light throttle after Transgo & Servo install
Well, got the Transgo shift kit, Corvette servo, and Superior OD servo installed yesterday. The only problem I am having is a SERIOUSLY harsh 1-2 shift under light and medium throttle. Under light throttle it clunks, under light-to-medium throttle it is harsher (sometimes chirping the tires). The only way around it is to go WOT. Of course, my neighbors wouldn't like me driving around at WOT all the time, so I have to find another solution.
I returned all of the tranny programming to stock in HPT (I think), so it would seem this is an install issue. Which parts of the install control the 1-2 shift? What could be causing the problem?
I returned all of the tranny programming to stock in HPT (I think), so it would seem this is an install issue. Which parts of the install control the 1-2 shift? What could be causing the problem?
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BINGO!!!!!!!!!!! AS I installed the same thing with AV yesterday, I too am having the exact same issue. I am hoping that tuning will solve this, I have no desire to tear back into this thing.
Naked, is your clunk audible? I have something similar but is on the 2-3 shift and only under 1/3 throttle. Seems inconsistent as well.
BTW THANKS for coming doen and helping out. It was a marathon..........
Naked, is your clunk audible? I have something similar but is on the 2-3 shift and only under 1/3 throttle. Seems inconsistent as well.
BTW THANKS for coming doen and helping out. It was a marathon..........
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If you didn't install any washers from the transgo kit, I can't imagine what could have gone wrong. Naked AV, I'm sure you didn't based on my install.
Could you try and lower your line pressures on the 1-2 shift via HPT and see what it does?
Perhaps on the seperator plate, the wrong holes were drilled? Or even the wrong size (e.g. Too large?)
Perhaps there is some binding on any one of the pistons that were changed out and/or removed? But that would mean tearing back into that thing again
Could you try and lower your line pressures on the 1-2 shift via HPT and see what it does?
Perhaps on the seperator plate, the wrong holes were drilled? Or even the wrong size (e.g. Too large?)
Perhaps there is some binding on any one of the pistons that were changed out and/or removed? But that would mean tearing back into that thing again
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Originally Posted by 02sierraz71_5.3
everyone has that problem put some of the tranny TM back in and adjust 1-2 table
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1-2 accumulator controls the 1-2 shift. I had the same problem when I had only one washer installed in the 1-2 accum. I actually returned the 1-2 accum back to stock (with the metal piston though) and with 0 TM it is MUCH more tolerable now.
Andrew
Andrew
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This is becoming more and more common a problem.
I have tried virtually everything to fix this issue.
As I use efilive I have access to different tables than HPT. EFILive has a "learn" table for each shift which allows the tranny to adapt pressure. I reduced those tables and it helped a bit.
I think in the end it may be the 1-2 feed hole. The Transgo is designed for the stock servos. With a Corvette or Billet 1-2, the feed hole size needs to be reduced to .63 or so.
Another route is a TB converter. A bit looser than stock should help soften the 1-2.
I have tried virtually everything to fix this issue.
As I use efilive I have access to different tables than HPT. EFILive has a "learn" table for each shift which allows the tranny to adapt pressure. I reduced those tables and it helped a bit.
I think in the end it may be the 1-2 feed hole. The Transgo is designed for the stock servos. With a Corvette or Billet 1-2, the feed hole size needs to be reduced to .63 or so.
Another route is a TB converter. A bit looser than stock should help soften the 1-2.
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Originally Posted by Eye-P
This is becoming more and more common a problem.
I have tried virtually everything to fix this issue.
As I use efilive I have access to different tables than HPT. EFILive has a "learn" table for each shift which allows the tranny to adapt pressure. I reduced those tables and it helped a bit.
I think in the end it may be the 1-2 feed hole. The Transgo is designed for the stock servos. With a Corvette or Billet 1-2, the feed hole size needs to be reduced to .63 or so.
Another route is a TB converter. A bit looser than stock should help soften the 1-2.
I have tried virtually everything to fix this issue.
As I use efilive I have access to different tables than HPT. EFILive has a "learn" table for each shift which allows the tranny to adapt pressure. I reduced those tables and it helped a bit.
I think in the end it may be the 1-2 feed hole. The Transgo is designed for the stock servos. With a Corvette or Billet 1-2, the feed hole size needs to be reduced to .63 or so.
Another route is a TB converter. A bit looser than stock should help soften the 1-2.
Thats not what I wanted to hear.
The funny thing is that it is not consistent. At relatively similar throttle levels, sometimes the shift is harsh, others its not. If in fact the computer can adjust, then it appears that sometimes the computer is adjusting others not. Theres seems to be a magic throttle position that creates the monster shift.
What if the servo was returned to stock? Folowing your logic Eye-P, would it soften the 1-2 shift?
It seems to be getting better.........
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Originally Posted by OCBC
What if the servo was returned to stock? Folowing your logic Eye-P, would it soften the 1-2 shift?
It seems to be getting better.........
It seems to be getting better.........
I'm not sure if it shows in the directions, but Eye-P is correct in that the feed holes are assuming a stock servo. I think when I did mine, I based it off of forum feedback and disregarded a lot of the directions. NakedAV and I constantly referred to the forum and online manuals on certain sections of the install.
However, I'd be hard pressed for just the feed holes alone being the sole reason that your experiencing what your going through.
Without being able to tune like NakedAV can ,you may have to wait till he fixes his. But I would be more inclines to tear into the tranny again to check the pistons you changed, and the feed hole.