[ChevyGuy1997]

I have a 2000 K2500, love the 454 that it has but recently found myself working on it a lot more. So i did some digging and found that an 8.1 will fit in the exact spot. Well, $800 and a few hours later i got a 2001 K2500 Suburban with an 8.1. Now, I can handle the physical part of swapping it, I need help with the wiring part. Any and all help is appreciated.

 

[jglew82]

Should be pretty easy. They used 8.1’s in the latest GMT400 heavy duty models. Look up a 2000 or 2001 C3500 (not Silverado) with 8.1 and you should find everything you need.

 

[davester]

I thought they stuck with their older engines in the GMT400's, and only once they switched to the gmt800 platform did they also get the 6.6 duramax/8.1l vortec engine.

 

[jglew82]

I thought they stuck with their older engines in the GMT400's, and only once they switched to the gmt800 platform did they also get the 6.6 duramax/8.1l vortec engine.

2001 Chevrolet K3500 GMT-400 4x2 Heavy Duty Service Truck W/Crane

2001 Chevrolet K3500 GMT-400 4x2 Heavy Duty Service Truck W/Crane, 99277 Miles Showing, Title Will Be Marked Miles Exempt, 1 Ton, 8.1L L18 MPFI Gasoline Engine, Automatic Transmission, Standard Cab, *NO AIR CONDITIONING, GVWR: Class 4: 15,000 Lb, Utility Box W/ Air Hose Reel, Oxy-Acetyline Hose...

www.bigiron.com

 

[davester]

Evidently they did put 8.1's in the '01 GMT400's.

IDK what GM did to get the 8.1 in there, but I expect the o.p. to basically have to do what's is needed for an LS swap into a GMT400, but IDK for sure.

 

[jglew82]

0411 and wire harness and basically plug and play.

 

[Markmx6]

LT1swap.com

That should have all of the wiring pinouts you need. The guy who owns the site has also been really helpful and shows you which wires you can remove safely depending on what you are doing.