Your correct Frank, heres the deal...sometimes it's a quick and easy way to prove/disprove tuning issues. A few years ago when we first started working heavy in these LS1's we noted that a manual valve body car was handling the h.p. alot better than the computer controlled cars were. We could easily put 800 plus H.P. through these manual units and couldn't get nowhere near that with the auto, without the 3/4 clutch burning up, we had a few other failures but by far the 3/4 was and still is an issure with these units. We have found that this burn up is primarly due to computer issues.....as these cars age we are finding a host of problems with reguards to the electronic controls on these cars. We don't tune cars perhapes we should start, I've always pointed our company in the machining direction opting for stronger/lighter parts. We have had alot of success with this 4L60e,never had one that we couldn't get shifting, I'm sure if we all work together we'll gets yours shifting as well. well I've rambled on too long gotta get going...sorry for the long post guys/gals...hope this helps ..Dave

 

F-Man, sounds like tuning issues. You should work with these guys and start from the ground up. When you troubleshoot an issue like this, you have to eliminate tuning as a suspect... Which in this case is probably the issue.

 

Could you elaborate on what you think the trans control issues
are about? I expect the PCM asserts various solenoid valve
open/close timings according to some invisible plan, and I also
think the tuner software folks could probably bring these out
into the light if we had some idea of what to look for. Like an
event overlap deal, or something? If you can put proper names
or sequences of events to it, maybe we can get people looking
for the handle.

 

if that "tire sanity check" number in grey...in the speedometer section isnt right...it will screw up wot shifts. it has to be close to the input tire size. i changed one for a guy yesterday...his tire size was 24.96 but the "tire sanity check" number said 33!!
"transrevolutions/mile" is the number to change to get them to match. I have seen this cause many not to shift 2-3

oh...would ANYONE here help Frank if he bashed THEM here and on other boards like he has RockOn?

 

guys i had similiar problem with my rebuilt not no 3000 dollars but 1000 dollars.it turns out i wot it hit rev limiter and not shift .so it took it back and it has the main pressure sensor or seliniod.then it has was perfect untill 1500 miles it wouldnt go into 3 or 4th.turns out some ring around the shaft that gos into the pump got damge.guy rebuilt the whole thing and tranny has had not one problem.i thought it was tuning but its not it the tranny.

 

we have used LS1 edit. my trans worked fine with the tune until it broke the second time. took it back to rock on they rebuilt it. thats when the 2-3 shift problems started. it would also not downshift out of overdrive or with a long delay. also had problems with wondering. wot it would upshift to soon then downshift. per advice from this thread paid $500 changed to HP tuners. it still did the same thing. i've decided to trash this POS & just start with a whole new tranny

 

tranny doesnt upshift too soon unless the pcm tells it to....
send me your hptuner file and i will look at it
Frank I ran a good bit more power than you thru Daves trannys and they all shifted fine when my tune was right. My first didnt shift 2-3 for the first 20 passes.....FINALLY found the problem in my tune and shifts suddenly started being perfect. It broke on a 1-2 shift when i sprayed another 100 shot on top!! We are talking in the 850rwhp range in a 3850# car with 3.23 gears....I loaded the **** out of his trannies to find the weakest links...turns out they are hard parts....my 3-4 clutches still looked great.
cablebandit@charter.net