vipergtrdj

Trying to figure out if the torque converter is slipping or trans clutches are shot. Attached is a log I did driving today, problem is when cold it drives great, no problems. Once hot it acts up, slips when taking off from a stop, reverse shudders (barely moves backwards), and feels like it just stops gaining above 4500rpms. Throw truck in Neutral and it revs up to 6000rpms no problems. I attached a screenshot of HPTuners showing the trans input and output rpms. I haven't ventured into the trans tuning stuff much but I would imagine the input and output shaft would be tighter together, not 2000rpms apart like that ?

I also attached the log if anyone wants to take a look at it in regards to transmission stuff. I'm currently in process of tuning for boost.

smokeshow

iTrader: (16)

3309/1332=2.48. that's first gear in a 4L80

Atomic

iTrader: (42)

Yea,
Input_RPM/Gear_Ratio = Output_RPM or you can reverse it to say Output*Gear = Input
Also,
Engine_RPM - Trans_Input_RPM = Converter Slip

madmann26

iTrader: (7)

What kind of converter?

Watching the log, your TCC Slip % spikes well above 100% in some frames. The more it's slipping, the less acceleration you're going to have. Possible causes:

1. Converter is toast
2. Worn TCC regulator valve
3. Leaking TCC PWM solenoid


Example: Between 17:21:39 - 17:21:42 TCC Slip % spikes to 156%. That's not good.

vipergtrdj

Well found out the transmission was trashed. Unsure what happened but I ended up loosing reverse, and it was slipping more on light throttle. So pulled it and in the process of rebuilding it. Hope to have it back in and running beginning of the week.

madmann26

iTrader: (7)

I hope you’re having the converter cut/cleaned or buying a new one.

If not, don’t expect the rebuilt trans to last long.

vipergtrdj

Buying a new one.