4.8 vs. 5.3, same truck and gearing...?

[mopower440]

wondering if anyone has ever had the same truck and same gearing but went from the 4.8 to 5.3 and if so, was there that much of a difference? I see the HP and torque numbers arent that far apart so wondering if there is much seat of the pants difference, stock against stock..iM ASKING BECAUSE I HAVE A 1999 ECSB 4X4 WITH 4.8 AND WHEN ITS SHOT I WAS GOING TO REPLACE WITH A 5.3 BUT IF NOT MUCH DIFFERENCE I WONT WORRY ABOUT WICH ONE I REPLACE IT WITH. nOT GOING 6.0 as it uses more gas and im not needing that much power, not racing or anything. sorry about the caps, computer flipping out.

[kerrige]

Don't let the numbers throw you I have seen plenty of 5.3 and 6.0s get better mileage than the 4.8s. The seat of the pants going from 4.8 to 5.3 wont be huge, but with a proper tune some simple boltons and a baby cam you could get great mileage and have your power too.

[RS/SS 4.8]

Yup get a 5.3. Ive driven both 07 rcsb 4.8 and 5.3 and i wish my truck had a 5.3

[00shortbox]

I'd go 6.0 if you could find one. I went from a 4.3 to a LS6 5.7 and am getting the same fuel mileage as the 4.3. And that's with no MAF and the fuel trims at +20%. Something is frigged up with my tune or MAF, won't run worth a crap with it plugged in for some reason.

[mopower440]

well, i kinda would like to go from the 4.8 to the 6.0 but afraid of the mileage. I know in this big extended cab 4x4 the 5.3 will get better mileage than the 4.8, but afraid the big 6.0 may get worse than the 4.8..? Also, i want the swap to be as cheap and painless as possble and dont you need more stuff to use the 6.0 than the 5.3, stuff like modding some of the wiring and different injectors or stuff?

[RS/SS 4.8]

As long as its the same year everyrhing should swap over. They are the same externally its the rotating assembly that changes.

[RedHeartbeat]

99 and some 2000s. If it has a flat flex plate it has the long crank snout. Some had a spacer you could remove but never trust that it's removable. If it has a flat flex plate, move on unless you're going to an older 80e or it comes with an 80e.

[mopower440]

99 and some 2000s. If it has a flat flex plate it has the long crank snout. Some had a spacer you could remove but never trust that it's removable. If it has a flat flex plate, move on unless you're going to an older 80e or it comes with an 80e.

are you saying the 1999-2000 are the ones i want or the ones to avoid?

[ecld_07]

are you saying the 1999-2000 are the ones i want or the ones to avoid?

yea if possible

[mopower440]

so ive been doing some more reading on this swap and its getting more complicated, not only did the early 6.0's have a longer crank, but so did the 4.8 and 5.3 also! My truck is a 1999 so the 4.8 in it is going to have the long crank, meaning the flexplate in it wont work with the 6.0...