4.8 to 5.3 swap

[Rudy67chevy]

would i have to swap the rear end also

[STOCKISH]

Nope. Rear is the same.

[nekkidhillbilly]

direct bolt in a and a waste of money if your going to swap go 6.0 or keep it 4.8

[torkerjr]

wouldn't you have to reprogram the computer also?

[hugger6933]

No reflash needed but it would help. I agree with the other stated above unless you are going to a 6.0 don't bother to swap. and by the way the 6.0 is a direct swap. Jim

[Joe67]

Originally Posted by nekkidhillbilly

direct bolt in a and a waste of money if your going to swap go 6.0 or keep it 4.8

x2 unless you have a line on a free/very cheap 5.3l.
I'd get a 6.0l truck motor at least. Very common swap on these trucks.

yes, you will also need a computer reprogram/PCM for this to work. Easy stuff.

[Rudy67chevy]

Would I need to swap the transmission? If I go with the 6.0
Posted via Mobile Device

[usmcchevy]

Originally Posted by Rudy67chevy

Would I need to swap the transmission? If I go with the 6.0
Posted via Mobile Device

Yes it will bolt up. Just don't expect the trans to last if you beat on it.

[ncl5047]

i know this is an old post but i was also thinking of going 4.8 to 5.3. why would it be a waste? jw thanks!

[clinebarger]

Its not a waste, Like going from a 305 to 350.
Reprogramming the ECM is NOT necessary, It will help if your trying to get every bit of power.

Ive done several 4.8 to 5.3 swaps, Customers love it especially when hauling trailers.

[67swb72klb]

what about a 4.3 to a 4.8/5.3 what would be involved in a swap.. pros/cons
just picked up a 07 gmc old body style std cab truck doesent seem too bad on power dont know about the gas mileage i will get with it ...

[hugger6933]

The 4.3 to 5.3 swap is a pain in the tail. The things that are different are transmission, engine wiring, computer[in some cases in others it is just a program] all of the cooling[ie hoses radiator etc] motor mounts exhaust lead pipes and the whole system in general. The front springs are different , as are the a/c lines. That is about all that comes to mind this time of morning I don't think the swap is one that most would want to take on unless you had a parts truck[that needs to be the same year] to make it all work, and the prices of those are steadyly climbing as I have found going to the salvage sales every week trying to buy more trucks. Oh almost forgot the fuel linesare different as well

[67swb72klb]

thanks thought it might be a option doesent sound like its worth it i will just roll with the 4.3 is it worth a re-tune or some other mods to pick up more mpg ??

[hugger6933]

4.3's are great motors. I've had a couple of hundred of them[Iam in the car /truck bussiness] You can do the normal things such as going to synthectic oils[for it to do best go one end to the other]k/n or other type hi-flow air filter and/or cold air type intake system. a freeer flowing exhaust will help too if you can stand the sound. Even after that your getting close to the end of what you can do,air pressures in the tires ,front end alignment and the cheapest, is driving style. Drive like you have an egg between the gas pedal and your foot will make a huge differece in the MPG's you truck will get. A reprogram will help and good deal.

[67swb72klb]

thanks for the input i will try the air cleaner and exhaust then a tune after that if i can find somebody local to do the retune thanks again hugger

[CAGRacing]

Hot rod magazine got 1200 HP from a twin turbo 4.8 with stock internals so I'd say there's some performance potential there.

[ncl5047]

Originally Posted by CAGRacing

Hot rod magazine got 1200 HP from a twin turbo 4.8 with stock internals so I'd say there's some performance potential there.

ive seen that before. didnt they think they were working with a 5.3 for a while and come to find out it was a 4.8?

[crazy longhorn]

Originally Posted by ncl5047

ive seen that before. didnt they think they were working with a 5.3 for a while and come to find out it was a 4.8?

Yup, & they could not figure why it made the power so high in the rpm band! crazyL