Installed CAD upgrade last night - fingers crossed

[MTTwister]

Haven't test driven it yet - too dirty to get in the truck, BUT -

1. The new CAD module started in nice and straight, but about 2/3 the way in, it looked like it was starting to cross thread. Couldnt' get it to 'straighten out, so I rammed it home as is. Have a feeling that it might be hitting the new "puck" and pushing the internal 4wd lever in the front diff into "lock" position - maybe I'm just a worry wart - but considering that:

2. The Harness - 88959465 - GM parts guy was sure thit is what I needed.
The 2 wire connector was incorrect -
The plug in recepticle on the harness was:
a - wrong size and shape, (too small)
b - Had "nail" type contacts, versus required 'blades',
c - had the blue wire from the actuator making contact with the black ground wire on the truck harness -if it would have fit it the first place.

Cut the wiring recepticle off the gas unit and spliced it onto the new harness (lining up the "B" terminal with the trucks blue wire).

Then I threaded the 3rd brown wire along the tranny oil cooler lines, securing with zip ties, instead of trying to snake it behind the starter heat shield - which would have put it within a 1/4" or less of the exhaust systems and all that Heat.

Believe I found the correct brown wire on the wiring loom over the tranny - knowing it was pin "D" on connector C120 - it had to be one of the 2 external wires - that helped narrow it down.
About 1.5 Hours total screwing sround time.
Will suck it up and test it tonight and see what I've got.

Anyone else have this much trouble on a 5 min upgrade?

[BobND]

FWIW,

hat brown wire actually connects to a power source that is switched with the key and fused through the 4X4 fuse.

Since it connects to the switch on the transfer case, I always figured it was switched there, depending upon 4X4 selection, but actually, it is simply connected to a power source for the new motor,

[MTTwister]

Yeah - fuse 24 - Hot in Run. But the wiring up by the fuse box looked worse than underneath. Today I'm not so sure ( sore all over soldering that connection) smile.gif

[tom.mcinerney]

What is "CAD module"?

[MTTwister]

Tom - The CAD is the Cnetral Axle Disconnect. Prior to '97 ( i believe) the 4wd's came with the doggy / sketchy gas expansion module, which relys on heating a gas to extend the plunger to engage the front 4wd. It has been known to disconnect if the dealie gets cold for whatever reason.
The newer one has an electronic motor - positive in- out action of the 'plunger'. Theoritically a direct and quick swap - although it requirs a 3 wire harness upgradt - the 3rd wire (brown)runs to a Hot in Run circuit ( fuse 24 also a brown wire) - normally 'suggested' to be tapped into the transfer case wiring on top of the tranny. ( Still getting the kinks out of my back after that soldering job - easy to see, but tough to get in there an work)

I had to do one more full turn to fully set the module to activate it. I could hear the motor run in / out, but I had failed to crank the dealie all the way in, and the 4wd light was still blinking.