12200411 PCM swap for 1996 to 2000 GMT400 trucks

[BOTTLEDZ28]

That extra wire is not needed on the 98s.

 

[BOTTLEDZ28]

Lextech can't figure out what the problem is so now I have to pay a local tuner to buy a license just so he can get into the ECM and delete EGR.!
I also have to mess with shift points since the stock ones that are in Lextechs tune, which I assume are the 2002 Express Van, are terrible. Trans shifts into second about 5 feet out from a dead stop at normal throttle and I'm in 4th with lockup about 50 feet out. It's annoying.

 

[Ss_single]

Anything for a 00 7.4 5 5speed?

 

[Mangonesailor]

I also have to mess with shift points since the stock ones that are in Lextechs tune, which I assume are the 2002 Express Van, are terrible. Trans shifts into second about 5 feet out from a dead stop at normal throttle and I'm in 4th with lockup about 50 feet out. It's annoying.

I noticed the excited shift from 1st to 2nd WAYYYYYY too soon as well. At first I thought it was only something I had ignored with the previous computer. Now I know I'm not the only one noticing this. If I floor it, it will shift from 1st-2nd at about 2700-3200 RPM. If I idle out, It'll shift at about 1600-1800 rpm. That's a good bit of lugging right there.

I still have a severe hesitation when in open loop when even lightly accelerating that I have to figure out. It may be my throttle blade position when shut, bad injector, or just part of the tune. Once it revs back up it accelerates fine. Its just that initial starting out from a stop in open loop. As soon as it goes in to closed loop, it stops.

 

[Spastik Monkey]

Does anyone make a plug and play harness for the swap?

 

[PolarBear]

Does anyone make a plug and play harness for the swap?

You can't be that lazy....

 

[Spastik Monkey]

You can't be that lazy....

My laziness knows no bounds

 

[496BBC]

Installing the 0411 in a 96 K1500 with 5.0, see a lot of talk about running wires form the trans harness to the PCM. My spreadsheet did not come with any info on doing this. Does anyone know if the 96 truck needs the gear select signal sent to the PCM. The spreadsheet is spot on in all other details so I'm guessing since it is not addressed in my spreadsheet they are not needed. Just wanting to make sure before I try to crank up the engine.

THanks Neal

 

[496BBC]

Well I got the swap done and decided to double check pin outs prior to cranking the truck. I had a few in the wrong spot so I got those corrected and gave it a shot. I cranked up and took a few minutes to straighten up but still labored too idle but then the MIL came on and yep the crank relearn. I performed the procedure and that straightened everything right up. Its shifting as normal so I guess the extra wires to the trans are not needed on the 96 K1500. Now to get a tune for it and take advantage of the 0411, then the BB install (8.1).

Neal

 

[Lextech]

All of the softwares (That I am aware of) now have the parameter that allows the 4 trans range switch wires to not be needed.

Jeff