2wd Ecu/pcm To 4wd?

[sbuchak]

I was wondering if i could use my 2 wheel drive 1997 gmc ecu to controll my 1997 4x4 truck??? Also prolly a stupid question but is there a difference between the chevy and GM ecu???

[bill190]

If they look the same on the outside, use the same electrical connectors, and have the same part numbers, then probably yes so long as you switched the PROM chips. If there is not a PROM chip which can be switched, then probably not.

 

Each PROM chip would be unique to each vehicle.

 

So far as chevy/GM being the same, same thing as above.

 

Basically they would like for ECU's to be the same and the differences being the programming in the prom chips (Or programming via a scan tool). However if you look at part numbers for these for various vehicles you will notice a HECK of a lot of different part numbers through the years!

 

I've noticed on other vehicles the same engine, same car, same everything, but different year and just one small variation on the ECU part number like last letter B as opposed to C. Then there are slight differences.

[Jennabear]

Short answer, yes, it is doable, however, you may have an issue with 4LOW operation. No need to worry about PROMs as they were not used in 97s. All 96+ PCMs use flashable memory.

[bill190]

Then I would imagine it would need to be reprogrammed with the correct information for the different vehicle.

[sbuchak]

Thanks alot guys you helped me out a bunch, I did the swap and the truck runs fine everything works except for the 4 low, but i wonder about the programming for it, I am not new to programming ecu' s ( Jap crap) just dont have the equipment for the chevy, so what do you think the dealership would say if i drove it to them to reprogram rather than buying all the stuff to do it my self? Or is there a resonably priced kit for the reprograming? Thanks again

[bill190]

Well the dealer should be happy to reprogram it for you. Especially if it is something simple and not much work. If you asked them to rebuild your engine, then they might not like that idea

 

And so far as I know, you would need a $3000 TECH II scan tool to do it yourself and I think the programming software is extra?

[Jennabear]

Yes the dealer can reprogram it for you, however it won't be easy. Everything is VIN based, so they will either have to have a custom program made (by GM Powertrain Engineering- VCI) or you will need to have them program it for another VIN number.

 

Realistically, it would take less than 10 mins to program it, however, it is them getting the proper information to flash onto your computer that will be the kicker. Expect to pay for around an hour of labor.

 

A Tech II is one of a few different types of hardware that can be used for this application. Any J5234 will work (along with a subscription to GMs SPS), the total cost of this would be $1500.