What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Doubeleive

Wes
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Thats what drove the discovery.
junkyard probably has one, just unplug the harness, grab a wrench and break it loose, then it just spins out, you might loose a couple ounces of fluid on the ground.
then you can either put the harness back on, hit the 4wd button and see if it works or not, or just apply 12v to the pins, sometimes they might barley move or move real slow. a good working one should move quick.
 

Fless

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Found out my four wheel drive is inoperative. Front axle wont engage. Transfer case shifts into all modes and ranges.
When in 4HI and with one front wheel off the ground I can turn it. Drive shaft doesn’t turn so I suspect the actuator or shift fork mechanism. Checked with the tech2 and the truck believes all is well with no codes anywhere and everything seems to respond correctly.

Make sure the grounds that are on the frame, behind the driver front tire and below where the driver's foot would be are clean and good. One of those, I think, may be for the front actuator. You can also unscrew the actuator and let it hang down, and push your 4HI button to see if it extends. If it takes more than a second or so, or doesn't extend at all, you may need to test the circuit or replace the actuator.

EDIT: If you haven't yet, use the Tech 2 to command the 4x4 modes. Make sure that what's commanded, and indicated on the dash switch, is what the Tech 2 shows is actual. As an example, mine had an encoder motor that would light the switch in 4HI (as selected) but actual mode was AUTO.
 
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cmatt

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Got the wiring done so the C-shaped led acts as DRL only and also will come on with the park lamps. Just waiting on parts to convert the old drl bulb to a park/turn signal. Then need to decide to move forward with the led projector retrofit.

DRL
2C5B9992-4464-464A-BC9C-A03550F87CFC.jpeg

DRL + park lamps
63D0F6CA-6904-4C3D-9A04-469CFF234C0F.jpeg
 

RooTBeeRthe1st

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Charged the batteries up since it's been sitting for weeks, getting started just long enough to move it from the street to the driveway and back a couple times.

Meanwhile I love truck has been taking up all of the driveway workspace and my time.
Might actually finish it today and be driving it tonight.

Then I will finally have a chance to start on the 14 bolt swap and see just what I killed in the 8.6".
 

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George B

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junkyard probably has one, just unplug the harness, grab a wrench and break it loose, then it just spins out, you might loose a couple ounces of fluid on the ground.
then you can either put the harness back on, hit the 4wd button and see if it works or not, or just apply 12v to the pins, sometimes they might barley move or move real slow. a good working one should move quick.

Make sure the grounds that are on the frame, behind the driver front tire and below where the driver's foot would be are clean and good. One of those, I think, may be for the front actuator. You can also unscrew the actuator and let it hang down, and push your 4HI button to see if it extends. If it takes more than a second or so, or doesn't extend at all, you may need to test the circuit or replace the actuator.

EDIT: If you haven't yet, use the Tech 2 to command the 4x4 modes. Make sure that what's commanded, and indicated on the dash switch, is what the Tech 2 shows is actual. As an example, mine had an encoder motor that would light the switch in 4HI (as selected) but actual mode was AUTO.
More clues…
There is a puddle of gear lube on the shop floor right under where the front axle actuator is.
 

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