I am the owner of a very tired 4.8 in my 99 Silverado, I have my hands on a very cheap and low mileage 05 L33 5.3, here I have been doing a lot of reading and have what it looks like 3 concerns, 1 program computer, 2 drive by wire throttle, and 3 something with long short crankshaft? Not sure on that one…So what I am thinking of grab my 4.8 intake and sencors, exhaust and hope I don’t have any crankshaft, Transmission mounting problems..If anybody has any fast or good ideas they would greatly be appreciated for this swap let me hear then..And thanks

 

should be an easy swap with everything working perfectly. just put the old TB on the newer engine so your linkage will work, everything else should be similar... the newer injectors will be bigger, so you will need a re-tune, but your stock PCM will control the 5.3 fine using your old TB.

no trans bolt up problems, crank should be the same.

 

while you've got the motors out, install a good cam into the 5.3.

 

Hey thanks guys, sickRED that would save time but if I stay with the 5.3 intake is there a fuel return line or not a return difference between my 99 and the newer 05 5.3?
And for a cam nick993, have any good ideas? Would like to stay mild but a few more hp cant hurt!

 

use all of your old stuff and you wont have to worry about anything... use your intake.. your fuel rails.. just leave them attached to your intake... use all your stuff and it will make it alot easier.. and its probably a good idea to pull the intake anyway and get new gaskets...

you might find a few things different but if anything is different than just use your old one.. like my oil pressure transducer was different on the 6.0 so i just took it off and put the one from the 4.8 on it..

its a very straight forward swap... someone with very minimal knowledge can do it in a day... i pulled mine sat morning and had it running sunday morning...

o and trust me i wish i wouldve put a cam in mine while i had it out.. i even had the heads off... but nope i put it back in stock... o well all in time...

as far as a cam goes.. you have to give us more info.. mild like still tow stuff.. would you be willing to change the converter??????

 

o and if you use all your old stuff (intake/injectors) then you wont really have to get it tuned.. it will run just fine on the 4.8 tune.. i promise.. im running my 6.0 on my 4.8 tune. it runs fine... now yes it is a good idea to get a tune.. but dont think it wont run without one...

 

You must re-use your alternator on the 5.3. Other than that, everything else swaps over from your current 4.8

 

his old power steering/alternator bracket should bolt up to new motor.. i dont know what your talkin about....

basically all you need is the long block.. block heads and oil pan.... everything bolts to the block and heads the same...

 

the cam i have my eye on is the comp cam 54-412-11. a guy on here recently installed it and it retained stock idle and drivability, and gained quite a bit mid and top end.

here's the link...https://www.performancetrucks.net/fo...d.php?t=435536

 

O.K the motors going in!!! Can I use my 2 line return 4.8 rails on the 5.3 intake, I would like to get rid of the EGR on the 4.8 intake and exhaust and then turn off the EGR in the tune???