eschweig

Hey all - newbie here so sorry of this is addressed somewhere else. If it is please point me that way.

I just installed the Transgo 4160e-HD2 kit and a corvette servo. I first had just the kit installed, but had slipping on 2-3 shifts and then installed the corvette servo and that problem was fixed. A new problem has come up where it almost red-lines before it shifts from 2-3 and 3-4 when anything greater then half throttle. The 1-2 shift is great and I can have it shift faster if I let off the gas.

Thanks for any help!

mrvedit

Hitting redline on the 2-3 shift is an indication that something is slipping - either the 3-4 clutch or the converter. If the only change you made was to install the corvette servo, then it sounds like the 3-4 clutch is seriously slipping.

Q1 - What year is your trans?

Q2 - Assuming it is pre 2006, did you remember to install the thick washer on the HD2 boost valve?
If not, your line pressure will be low and everything will slip.

I wonder if when installing the corvette servo you messed up the sealing ring on the 2nd apply piston and it is leaking 3rd apply fluid, causing the 3-4 clutch to slip.

Q3 - How big did you drill the 3rd apply hole in the separator plate? .093?

Q4 - Also, did you install a different converter at the same time?

In short, if the tune and converter did not change, you might want to double-check the assembly of the boost valve and the servo. And/or you might want to have a trans shop check the line pressure for you and have an experienced mechanic "feel" the shifts. It is also possible that the 3-4 clutch is failing and the symptoms are changing as it fails.

eschweig

Thanks, for the info. I believe it is as old as the car so 1995, if the washer came with the kit then yes. I was pretty careful installing the servo but I guess the ring could have slipped. I drilled it to .093 and no other converters. I did read somewhere that maybe a check ball could be have slipped when I was putting the valve body back up and also some said not to drill the plate and to get a new one. It is no longer throwing any codes.

mrvedit

Checkballs "close" when a clutch is activated, forcing the fluid through a small feed hole in the separator plate to control how fast/firm the shift is. The checkball then opens when the clutch is released, allowing it to release very quickly. If you forgot a checkball, one of the clutches (or band) would engage abruptly, but certainly not slip. Of course putting a checkball into the wrong position would give a very strange symptom.

Has your 1995(?) trans ever been rebuilt? If not, 18 years is an long time for the marginal 3-4 clutch to survive.

eschweig

not sure if it has or not.

pricesgarage

probley the 3-4 clutch pack is bad the kit incresced psi so it would work better at low rpms also if the band is worn i never recomend shift kits in older trans because of this

joecar

He maybe means where a checkball embeds itself into the separator plate.