LS1/T56 fuel mileage poll

[Michael D]

So, I think the next stage for the ol' truck is probably gonna be an LS1/T56 swap. I'm curious what the mileage is gonna be like though. If responding with mileage, please include mods, gearing, tire size, etc. I could use the current 3.42's, but 6th wouldn't really be useable. 4.10's seem like they should fit the bill, but lemme hear what you guys are running. Thanks.

 

[silverado13]

i know a LS1 T56 fbody can get 28-30 on the highway, thats what my buddys cammed camaro was getting, but the truck is like 1500 pounds heavier plus AlOT less aerodynamic, so im really not sure, if i had to guess though id say 18 city and maybe 22-23 highway if you drive it conservatively

 

[sewlow]

Don't know if I could drive a LS/T56 conservatively! Lol!

 

[silverado13]

well why ls1? i mean ls1 is a great engine and all but a LS2 is better, or even go with a conventional truck LSX like a LQ4 or a LQ9

 

[Horns]

My friend's LS1 T-56 Goat get's 14 in the city and 21 on the highway when the air is cold enough. Normal days around here it's 13 in the city and 18 on the highways.

 

[silverado13]

yeah if you are going for mileage the best thing is to park the truck and buy something lighter, thats the only reason i didnt do that swap, that and i dont feel like having to find a divorsed transfer case to keep my 4wd (that doesnt work right now)....

 

[96-1500]

yeah if you are going for mileage the best thing is to park the truck and buy something lighter.

This. Trying to eek out a bit better mileage out of a current setup is always smart, but in the end we drive big heavy boxes on wheels, you aren't going to see anything amazing.
I've never done the swap but I know people who have.

 

[Michael D]

well why ls1? i mean ls1 is a great engine and all but a LS2 is better, or even go with a conventional truck LSX like a LQ4 or a LQ9

Simply because LS1's are a dime a dozen. I can pick up a running/driving LS1/T56 Camaro or TA around here pretty routinely for under $3k. I'll be able to pull everything that I need or want for the swap, and still be about to part out or sell the rest. An LS1/T56 combo, with the harness, is tough to beat for what I plan on having invested in it. If I could find a cheap donor LQ4 or LQ9 truck, I would maybe go that direction, but for reason people around here think they're worth way more than I do.

 

[Michael D]

yeah if you are going for mileage the best thing is to park the truck and buy something lighter, thats the only reason i didnt do that swap, that and i dont feel like having to find a divorsed transfer case to keep my 4wd (that doesnt work right now)....

I've got plenty of lighter things, but I like cruisin' my truck. I'm not looking to set the world on fire or anything, but I do plan on at least doubling my current mileage.

 

[silverado13]

Simply because LS1's are a dime a dozen. I can pick up a running/driving LS1/T56 Camaro or TA around here pretty routinely for under $3k. I'll be able to pull everything that I need or want for the swap, and still be about to part out or sell the rest. An LS1/T56 combo, with the harness, is tough to beat for what I plan on having invested in it. If I could find a cheap donor LQ4 or LQ9 truck, I would maybe go that direction, but for reason people around here think they're worth way more than I do.

small correction, LS1s arent exactly a dime a dozen, i mean they arent by any means hard to find but if your going off of that concept then why not just get a 5.3 out of a truck, now those are a dime a dozen, im curious the production numbers between vehicles with 5.3s vs. LS1, i bet its a huge difference