I currently have a 94 K1500 and want to upgrade my dash to the newer style. Along the change, I will be ridding the truck of the Vac system and using a boost controller. I have a deal pending with a forum member for a newer engine harness and dash harness as well as ECM that will be turned up. I am concerned that the wiring (engine side) may not fit my components i.e., glow plugs, etc. Has anyone tried this before? I already have the 98 door cards and panels (not wired yet) and would like to complete the look. Any advice or opinions are welcome and encouraged.


jamminGMC:D

anyone?

what newer year harness are you upgrading too? you may encounter slight plug differences especially at the engine management harness to the ECM. Now you will be limited to not getting into the OBDII style engine management system because there is a lot of little add ons you will need as upgrades from your '94 system. I am not 100% sure if the reading connection from the engine harness to the body harness is the same either it may or may not have the same amount of wire connections (newer models most likely have more wires). Now you will most likely run into a transmission interface issue 4L60E vs. 4l80E difference in year plug issues GM didn't like to keep it simple. Your best bet is to get the entire kit and kabootle off a donor vehicle. This way you can change everything to the updated year components.
Either way you are looking at a lot of (worthwhile) work. try and find the GM electrical books for the years you need, this will help you trace out the proper color combinations and proper locations of pin placements and so on.

'94 is OBD-I, '98 is OBD-II - world of difference thruout, but engine\IP sensor connectors are same.

'98 has electronic passlock system, usually requiring steering column, which is a critical part of system.
Can be defeated with dealer help, iirc.

If you're just upgrading the inst cluster, that's all you need.

If it's the entire OBD EFI system, you'll need the complete engine bay and cabin wiring harnesses

'94 is OBD-I, '98 is OBD-II - world of difference thruout, but engine\IP sensor connectors are same.

'98 has electronic passlock system, usually requiring steering column, which is a critical part of system.
Can be defeated with dealer help, iirc.

If you're just upgrading the inst cluster, that's all you need.

If it's the entire OBD EFI system, you'll need the complete engine bay and cabin wiring harnesses

upgrading the entire wiring system under dash, to the doors and engine harness from a 96 and the dash and steering column are from a 98. Looks like the steering column wont work..... Maybe I can find a 96 model column and should be in good shape???

jamminGMC:D

What is the problem with the steering column?

anyone?


I think all the diagrams showing how to wire the plugs is listed on fullsizechevy

What is the problem with the steering column?

the newer dash has a larger opening and my steering column wont look correct in the huge opening:eek:



jamminGMC:D

I think all the diagrams showing how to wire the plugs is listed on fullsizechevy

I believe that you are correct, but I also believe that they are for gassers:confused:


jamminGMC:D

quote "the newer dash has a larger opening and my steering column wont look correct in the huge opening" quote

I believe that '95 and up columns are the same, '95 was the change over year. The '98 column should be the same as a '95 or '96, your '94 column is smaller in diameter.

quote "the newer dash has a larger opening and my steering column wont look correct in the huge opening" quote

I believe that '95 and up columns are the same, '95 was the change over year. The '98 column should be the same as a '95 or '96, your '94 column is smaller in diameter.

yep, and that is why I need to change the steering column. someone asked earlier "what is wrong with the steering column?" and I must say that mine is perfect, just for a 94 and I would really like to go with the 95 and newer.


jamminGMC:D

ok, need some more info....Does a 96 model have wheel speed sensors?? I am not sure if my 94 has them or not:confused: . Anyone know of any other potential problems?


jamminGMC:D

ok, need some more info....Does a 96 model have wheel speed sensors??

Mine does.

great, something else to change...lol