99 c2500 crew cab short bed Fuel tank swap or aftermarket xl tank?

[Frank Enstein]

I'm putting a 42 Gallon auxiliary tank in Frank from my Sub.

 

[Supercharged111]

I'm putting a 42 Gallon auxiliary tank in Frank from my Sub.

That only works in a long bed.

 

[bigbuddy2500]

With the goal of trying to fill once a week an aux tank with a transfer pump would probably be best. I drive about 200 to 1000 miles a week, which is why I'm looking for new cloth bucket seats or the 60/40 with a center console. And when this 5.7 vortec quits I'm about 90% sure im going to swap in a lq4 without afm or rebuild one with an afm delete kit. I'll look for a post about the swap, off the top of anyone's head, will the 4l80e from my truck work with a lq4 ecm? or would I need new sensors? I dont mind modifying the harness to plug and play so long as there's no issues with the electronics

 

[stutaeng]

...off the top of anyone's head, will the 4l80e from my truck work with a lq4 ecm?

Yes

 

[bigbuddy2500]

Yes

Plug and play with some modifications to the wiring harness? Will likely splice the old one with the new one with the lq4 ecm/ harness. Is lextech still active? I was watching some YouTube videos and he is usually mentioned as a source of good information

 

[stutaeng]

Plug and play with some modifications to the wiring harness? Will likely splice the old one with the new one with the lq4 ecm/ harness. Is lextech still active? I was watching some YouTube videos and he is usually mentioned as a source of good information

Get a complete engine/ECM/wiring harness from a 2500 SUV/truck or 2500HD+ truck. No messing with wires or splicing.

Edit: you are thinking you could keep and modify your existing wiring...not sure I've seen it done that way. Not sure on that...

 

[df2x4]

Is lextech still active?

He is, here's his thread on the 0411 PCM swap. If you click on his user name you can send him a message.

https://www.gmt400.com/threads/12200411-pcm-swap-for-1996-to-2000-gmt400-trucks.9644/

Edit: you are thinking you could keep and modify your existing wiring...not sure I've seen it done that way. Not sure on that...

Lextech sent me a spreadsheet for swapping an LQ4 into my red '97 a couple years back. Been a while since I've looked at it but I think you can keep a lot of the existing wiring and re-pin it to the 0411 PCM.