HPT Trany Help please
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Joined: Apr 2008
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HPT Trany Help please I've got a LS swap car (78 Malibu) '03 Suburban 5.3 backed up by an '07 4l60e. The engine has '02-'06 LS6 cam and springs, cold air intake, exhaust manifolds w/3" dual magnaflows, otherwise stock straight out of the sub. The trans has 38,xxx miles, I put a stock converter w/the stator modified (gives 300-400 rpm over stock) and I put in a TransGo HD2 kit (in car mods) in it.
I'm a afraid I might have already killed the trans. I've read alot and made improvements but this morning I Dropped the max pressure and shift pressures (upper end of scale) to 80 from 96 and now the trans slips in 2nd and blows out of the vent.
I think that between the shift kit and raising the max presure to 96, I've damaged the 2nd band (bent tabs?).
A tranny sticky covering what NOT to do under any circumstances would be great. As I have found limited info on trans tuning and what I have found is pretty dated as to what version of the software was used.
I'm a afraid I might have already killed the trans. I've read alot and made improvements but this morning I Dropped the max pressure and shift pressures (upper end of scale) to 80 from 96 and now the trans slips in 2nd and blows out of the vent.
I think that between the shift kit and raising the max presure to 96, I've damaged the 2nd band (bent tabs?).
A tranny sticky covering what NOT to do under any circumstances would be great. As I have found limited info on trans tuning and what I have found is pretty dated as to what version of the software was used.
The main thing I got from reading up on trans tuning was to not increase the pcm line pressure with a shift kit as it already affects that mechanically. Does it still work if you put it back to 96?
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TECH Regular
Joined: Apr 2008
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Better. But damage is done. A buddy has a trans from an '05 or so trailblazer ss that he will loan or sell me. Probably put it in stock and swap to a 4l80 over next winter when I install turbocharger.
I can't say whether you've medssed it up, but starving it of pressure
where it need it most, is a bad idea.
Begin by putting it back to (say) 95% max at the big end and see
whether it works. There is no reason to go less than stock profile
unless you've really jacked with the base mechanical pressure.
Be sure your force motor table's 100% column has a low (~90)
and not a high (1000ish) mA value. Otherwise when you up the
max line limit value you can step into a blowoff.
where it need it most, is a bad idea.
Begin by putting it back to (say) 95% max at the big end and see
whether it works. There is no reason to go less than stock profile
unless you've really jacked with the base mechanical pressure.
Be sure your force motor table's 100% column has a low (~90)
and not a high (1000ish) mA value. Otherwise when you up the
max line limit value you can step into a blowoff.
