I have been having issues again lately, now the trans Flares VERY badly on the 2-3 shift and pretty bad on the 1-2 and 3-4 shift. But when it does it with the 2-3 shift it feels like the trans is going to fall out of the truck. Stuff comes flying out of the cubby, the truck feels like it jumps up in the air. If I let off of it right before it shifts then it is fine, but if i missjudge the timing... BANG!!!!!

I dont know why, it was running perfect yesterday, I reloaded the 01TCM that was in it before, reset the TAPS, and it still does it. I am having a coronary!! HELP!!

I loaded the stock tune back into the ECM and the TCM, it was still doing it, then it stopped and I did a WOT run and it was fine, then it started doing it again!

I am at my wits end!! Still no Codes!!

with my stock tune at WOT it shifts perfect sometimes, also with little to no throttle it shifts perfect. but right in-between it flares the shift soo bad.

I loaded an old tune today, ran it, when the 2-3 shift came up i didnt let off and as soon as it shifted into 3rd after the flared shift and BANG, it lit the tires up and the truck went sideways, the downshifts are getting ALOT worse too, I stopped at a red light, fairly quickly and literally about 2 seconds later the the truck jumped forward, if I hadnt had my foot on the brake as hard as i did the truck would have been in the middle of the intersection. WTF is going on! Still no codes!!

I'd put a Tech 2 on it, period. I'd go into the diagnostics area and punch in all slip codes i.e., P0731 on through P0735 and see what pops up.

When you turn the ignition switch on does the CEL light? Reason for this question could the light (CEL) be bad and not show that there's a code?
I also know sometimes codes are in there that slip by the CEL--don't ask me how--I don't know how or why.

Can't understand how it works, then doesn't, I don't believe it's trans related. You've stated that occurences are the same a problems in the past--what were these codes?

Sorry one more observation: Race tune, EFI Live--you're not playing with the TCM tuning are you? I have no experience with EFI but I've heard that Allison really doesn't like it when you play with her there.

Mine does it. Tuning helps. But when I floor it.....its on.

You gotta check it with a Tech II.

i dont have access to a Tech 2, i can input TAPS values via EFI, is that the same as the slip codes?

i dont have access to a Tech 2, i can input TAPS values via EFI, is that the same as the slip codes?

No the "slip codes" I'm referring to are the trouble codes that are stored when there's a trans problem P073-series codes are "incorrect gear ratio" codes which usually indicate clutch slip.

I talked to George at Suncoast (awesome guy!) he thinks the internal filter may have fallen out, or is about to fall out, so I am going to pull the pan tomorrow after work and replace the internal filter, and put on a new spinon and magnet. I really hope this fixes it! -Jeff