Official NBS V6 to GENIII V8 swap Guide
#451
After weeks of trying to figure out my clutch position switch issue, I decided to tear the old dash harness for the 2005 GMC Sierra apart and traced all the wires. I took the harness inside and tore into it. I left all the wires that were for the v6 cruise control and connector underneath the dash cover right above the cluster. It's the connector were the brake switch and clutch position switch plugs into. After tearing the harness apart, I compared it to the the 05 Tahoe fuse block dash harness connector and noticed two wires were missing. The Green wire in position A11 and the Pink wire in position F6. The pink wire splits into two. One wire goes to the connector and the other went to the connector for the cluster. Therefore, instead of running the pink wire to the fuse block, I just tapped into the pink wire at the cluster connector.
I temporarily ran the Green wire to position A11 on the 05 Tahoe harness and now the clutch position switch works as normal. The rest of the wires in the last few pictures are for the v6 cruise control. Since I have no intensions on swapping it to a v8, I think I'm going to run the wires for the factory cruise control.
I temporarily ran the Green wire to position A11 on the 05 Tahoe harness and now the clutch position switch works as normal. The rest of the wires in the last few pictures are for the v6 cruise control. Since I have no intensions on swapping it to a v8, I think I'm going to run the wires for the factory cruise control.
#453
100% Redneck
This is my cut based on my test fit...
I set the engine in temporarily with the intake to measure where to cut. It was easy to set the engine in the engine bay, measure, then pull out due to no radiator core support. If this is not an option and you are using the part numbers in this thread... the photo above will give you a idea where to cut.
Engine test fit
This is where the braided lines laid during the test fit
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strutaeng (09-20-2022)
#456
100% Redneck
I took a lot of photos for reference when I started pulling everything apart.
In this photo it barely shows a blue plug (arrow). If you can blow up this high resolution pic you can see the blue plug under the arrow... I believe is the top half of that blue plug in your photo. It shows a black wire with a white tracer.
In this photo it barely shows a blue plug (arrow). If you can blow up this high resolution pic you can see the blue plug under the arrow... I believe is the top half of that blue plug in your photo. It shows a black wire with a white tracer.
#457
#458
100% Redneck
I don't think those two plugs are on the engine harness. IIRC they are under the fuse block. I forgot to connect the blue plug and during my initial fire up my tach didn't work and my fuel & other gauges read backwards. Digging in... I connected the blue plug and my tach and cluster gauges were now operational.
#459
Engine harness
Hey guys im currently in the middle of this swap I have a 2004 Silverado 1500 doing the V8 swap 5.3 L currently having issues with engine harness. I am using the engine harness from a 2000 Chevy Tahoe currently have no Crank no start truck is originally drive by cable, what is the harness would i need?
#460
makes children cry
iTrader: (5)
yep... it's only been stated in here a million times that the 99-02 harness is different than the 03-07, and you need to get a harness & computer that matches the year of the truck. for the 03+ guys who want to keep the throttle cable (versus an electronic pedal swap), you'll need the harness from a van.
if yours is a manual trans, you'll also need to ensure there's a jumper wire in the fuse block for the clutch safety switch.
if yours is a manual trans, you'll also need to ensure there's a jumper wire in the fuse block for the clutch safety switch.