chumscustoms

iTrader: (1)

I have just purchased a 5.3 truck motor (1999)
and i have a gxp 5.3 dod motor, can i use the short block and heads from the gxp and for my truck motor
I am swaping it all into a 63 nova but the truck motor has high miles so i figured i could use the dod motors long block
any input will help
thanks

Bryan921SS

Maybe, but you have to remember the LS4 is a very different beast....the valley cover is different on the LS4 than it is on the 5.3 engine (because they are completely different engines(LS4 aluminum, 5.3 iron) and there is a sensor mounted on the cover that is hard to get around...if you use a different valley cover then maybe...the heads are from the LS6 so those would bolt on...why do you want to combine an engine designed for MR/FF applications with an engine designed for FR applications in the first place???

LS4SPEED

iTrader: (3)

I believe there is an aluminum block 5.3 ltr that is not an LS4. Not sure if that is what your talking about. I think it came in the GMC Envoy Denali? I'm probably wrong who knows. But you can't use the block from the LS4, it has no starter mount. But you could always make a bracket I guess.

EDIT; Yes there is an aluminum Vortec 5300, its available in the Trailblazer EXT and Envoy XL. 5.3 liter Vortec V8, available in the 2003 and later models. Not the 1999.

neilownz

Get the truck motor refurbished. My LQ4 has 180k on it with no problems. Not sure the specs or if the heads will work well. Head over to performancetrucks.net (link at top of the page) and search a little bit then post something about it if you cant find what you're looking for. Alot of people run 4.8s and 5.3s with a head/cam/etc swap, but people will respond with like get a 6.0l probably...

Bo185

No the GXP uses the LS4, and that block uses the 60* bellhousing vs the Gen III regular SBC so it won't bolt up to your transmission if its a regulaur 700r or th350 etc...

The LH6 is the DOD traiblazer motor is all alumuinm 5.3l and is a regular truck motor.