4.3 To 6.0 Swap-99 C1500

mbumgua · September 12, 2007

Looking for advice. experience or opinions on swapping out my 99 4.3 5 speed for a 6.0 out of a 2002 c3500hd with automatic. I bought a wrecked truck off of ridesafely.com and got a decent deal on it. Engine and trans were not damaged as it was a light rollover.I want to change rear end and front brake rotors as well. Anybody have any warnings or caveats about this swap? Thanks in advance for your comments.

Tucson_02Silverado · September 12, 2007

others will chime-in;

If I remember right, the 2500/3500 6.0 with auto was the 4L80E and the manual that was available was the ZF6 6-speed. So getting the 6.0 to work with your 5 speed would need custom programming. Sticking with the auto from the 3500, you would need the column from the 3500 truck, or the like, for the auto shifter. Then you have to deal with the hole in the tranny tunnel and clutch pedal/linkage. The closest to a stock 2500/3500 ECU programming with the ZF6 would be to replace your T5 (at least I think it's a T5) with a T56 from an F-Body.

If the cab/bed styles are the same just swap the body from the 99 to the 02. The only problem might be since the 02 VIN has a salvage title, even with a new body/parts would still be a salvage (state by state dependent).

mbumgua · September 12, 2007

Yes I plan to use the 4l80E and steering column out of the wrecked truck. I had planned to switch bodies as the frame was not damaged but the wrecked truck turned out to be a long bed ext.cab and mine is short bed. I have done auto to manual swaps and manual to auto swaps before in older chevys, just not on new ones. I did a 4.3 to 5.3 for my brother in July --c1500 to c1500 and he really likes the power difference. I plan to use the pcm, bcm, gauge cluster and applicable wiring out of the wrecked truck. Airbags did not blow on wrecked truck. I know I have to route the shift cable through the floor. Does anyone know if there is a knockout or something similar for the cable? Thanks

Wingnut · September 13, 2007

Yes I plan to use the 4l80E and steering column out of the wrecked truck. I had planned to switch bodies as the frame was not damaged but the wrecked truck turned out to be a long bed ext.cab and mine is short bed. I have done auto to manual swaps and manual to auto swaps before in older chevys, just not on new ones. I did a 4.3 to 5.3 for my brother in July --c1500 to c1500 and he really likes the power difference. I plan to use the pcm, bcm, gauge cluster and applicable wiring out of the wrecked truck. Airbags did not blow on wrecked truck. I know I have to route the shift cable through the floor. Does anyone know if there is a knockout or something similar for the cable? Thanks

I'd love to do a 5.3 swap in my truck.

Tucson_02Silverado · September 13, 2007

The 4l80e into a 2wd shouldn't be much problems at all. It's longer so there will be a need to fabricate tranny mounts. I haven't been under my truck much...but if the General did anything like in the 80's/90's with the Caprice, there was two sets of mounting points on the frame, so the tranny crossmember had to slide back for a TH400 (4L80) from its 700R4 (4L60) location.

I think if you could swing a little extra $ putting in a T56 6 speed in place of your 5 speed would be a lot less metal/dash work. Just harness modification and ECM programming.

Wingnut...Fred needs an LS7 with it's matching red intake covers.

Zembonez · September 13, 2007

[i'd love to do a 5.3 swap in my truck.

If you do the Fred 5.3 swap, I might just have to hire the duct tape bandits to come take it away from you.

I'm sure you'll understand.

mbumgua · September 13, 2007

The 4.3 to 5.3 is pretty easy if you have a wrecked truck to get parts from and well worth it for the performance gain. Fred would really benefit from this transplant. If I had stuck with my original plan to swap 4.3 for 5.3 I could have kept my 5 speed light duty trans--But no-- I wanted the extra towpower with the 6.0 and couldnt find one with a hd manual trans.