Is this possible???? Experts needed for this one

[johnj]

What all signals are needed to control the 4L80 other than transmission sensors. At work we are currently in the process of doing a 12 valve cummins swap into a 2002 suburban. The customer was worried that his 6.0 was going to give up on him at only 200k and wanted something more reliable. We tried to inform him that the LS platform is known for longevity but he didnt want any part of that and wanted to switch to a diesel engine. So here we are finishing up a swap into a perfectly running truck and need to figure out if we need to use an aftermarket trans controller or if we can use the factory computer. We have crank signal, coolant temp, volts, and oil pressure all still going through the factory computer and dash so i figured we might be able to control the 4L80 as well. If i fail the maf like if i was running speed density would it shift normal or do i need to have cam signal and other things as well?

[joecar]

You will need VSS (from trans or transfer case (or axle shaft if Corvette)) and TP (throttle position)... you may also possibly need MAP which you should have anyway.

You will also need a P/N switch (so PCM can select the PN or IG idle tables).



In SD, you need to edit the Trans DTC/fault tables to disable max pressure on the MAF DTC's... AND you must ensure that the VE table is tuned correctly (i.e. does not report low) to avoid line pressure being under-calculated (as this would allow slipping which you know is fatal to the clutch/band brakes).


CKP/CMP are not used for trans control, but are used for engine control so you will need these anyway... without CMP signal, PCM does figure out correct crank phase, but CMP signal allows it to verify what it's doing (and possibly allows misfire detection to work properly, not 100% sure on this).