4160e shifting problems
#1
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INFO its a 4160e tranny rebuilt with a transgo shift kit with three washers and vig 3500 stall..
okay got the car tuned by pcmforless the first tune he did seemed to be good
the only bad thing was tht he upped the line pressure in the transmission from 90 which is stock too 120 for a much firmer shift..... well its way to high with the shift kit
the car would band into second at four grand at 20mph chripping
but took the car to the track ran it five passes and it shifted fine at 5800 and rev 6400
then second tune he raised the shift points too 5800 then rev to 6500 the with 95 psi in the tranny....took it down the road and got on it the car would hit rev limiter then shift in tirst gear
then the third tune it did it in second and not first so i called him and told him what was going on he said hell put a stall wall in it???
what is tht he said bout adjusting the mph for the shift sound true?
makes no sense cuz from the first to the second tune he only raised the shift point by 100 both ways whys it hitting rev limiter now??
okay got the car tuned by pcmforless the first tune he did seemed to be good
the only bad thing was tht he upped the line pressure in the transmission from 90 which is stock too 120 for a much firmer shift..... well its way to high with the shift kit
the car would band into second at four grand at 20mph chripping
but took the car to the track ran it five passes and it shifted fine at 5800 and rev 6400
then second tune he raised the shift points too 5800 then rev to 6500 the with 95 psi in the tranny....took it down the road and got on it the car would hit rev limiter then shift in tirst gear
then the third tune it did it in second and not first so i called him and told him what was going on he said hell put a stall wall in it???
what is tht he said bout adjusting the mph for the shift sound true?
makes no sense cuz from the first to the second tune he only raised the shift point by 100 both ways whys it hitting rev limiter now??
#3
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It is difficult to be sure without comparing the two tunes.
It is not all that likely and I hope not, but one logical explanation is that the lower line pressure is causing the trans to slip.
I would suggest going back to the higher line pressure and taking two washers out of the 1-2 accumulator. (Only need to drain the fluid, drop the pan the remove the accumulator with 3 small bolts to do that.)
But, I'm no expert, so lets see what others suggest.
It is not all that likely and I hope not, but one logical explanation is that the lower line pressure is causing the trans to slip.
I would suggest going back to the higher line pressure and taking two washers out of the 1-2 accumulator. (Only need to drain the fluid, drop the pan the remove the accumulator with 3 small bolts to do that.)
But, I'm no expert, so lets see what others suggest.
#5
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The three washers in the 1-2 Accumulator do not increase the pressure, they decrease the shift time - hence the super hard 1-2 shift. The accumulator cushions the shift like a shock absorber. Putting in more washers both decreases the volume in the accumulator and stiffens the spring(s).
If my hypothesis that the trans is slipping at 90 psi pressure is correct, then there is a problem. A fresh rebuild should not be slipping. Alternatively there might be a converter problem, but I know nothing about converters. Still hoping someone else has knowledge/experience with your problem.
However, most people would probably check the tune first.
If my hypothesis that the trans is slipping at 90 psi pressure is correct, then there is a problem. A fresh rebuild should not be slipping. Alternatively there might be a converter problem, but I know nothing about converters. Still hoping someone else has knowledge/experience with your problem.
However, most people would probably check the tune first.