Chicago TDP

iTrader: (3)

Wire brush it and wash the motor out.
Blow it dry, WD40 it and re-assemble.....

Snkebait95

iTrader: (16)

Thats most likely a 4.8l. You can tell by the different rod casting numbers. Or since its already down to the shortblock, just measure the stroke roughly by rotating a piston to bdc and stick a tape measure down the cylinder. Itd be roughly 3.6 in. for a 5.3, and roughly 3.25 for a 4.8l. I accidently bought a 4.8l before doing the neccesary research.

alexcoreas

iTrader: (1)

Just searched and mine is a 5.3 only 5.3 were offered in 02 avalanches.

RabidStreetRacer

iTrader: (1)

I believe that is only like 1999-2002 without the MLS gasket. I have a 1999 with the tab and had to make sure i ordered the right gasket set. was told they were the first 2 or 3 years of the 4.8/5.3

pairof69s

not saying much but my 150,000 Lq9 looked somewhat better,,,,,

94'BLKBRD

iTrader: (76)

My 2005 4.8 has the head gasket tabs sticking out.

RabidStreetRacer

iTrader: (1)

I see, maybe I misunderstood the guy at Napa.

some dude

One of the heads is cracked. My 4.8 looked just like that and it had a cracked head. Causes crankcase pressure to build up faster than the pcv can keep up and chuggs oil into the pcv valve through the driverside valve cover. I bet the intake was full of oil wasnt it.

some dude

And some 5.3s had flat top pistons. Not manybut some do. You have to get the cast numbers off of the crank to know for sure. Or measure the stroke.

-TheBandit-

iTrader: (1)

x2. And of course make sure the cylinder you're measuring is at bottom dead center when you take the measurement.

a4ls2goat

That in the pic is a 4.8.
5.3 have dish pistons.

phluxx

This doesnt always hold true, 5.3s come factory with flat tops aswel

Michael Yount

iTrader: (1)

....and that provides absolute certainty only if you are absolutely certain that the donor vehicle never had its engine replaced. For absolute certainty, measuring or examining the engine is better than relying on tags, markings and VIN numbers.

Fast355

Absolute truth. I myself have put more than one low mileage $350 junkyard 4.8 in a 5.3 truck I was flipping! I have also found a 4.8 in a truck that was supposed to be a 6.0L! Throwing a cheap engine in a truck to get it back on the road is not really unusual on a 10+ year old truck.

Michael Yount

iTrader: (1)

LOL - always makes me chuckle when someone posts "what rear gear do I have" and someone replies - "look at the tag"....maybe, maybe not.

Ryan Parker

Epic. This slayed me

donwp

I have an 06 Trailblazer with a 5-3 motor in it. will a 07 4.8 work or how much will I have to change

G Atsma

Depends if the 4.8 is Gen IV or III. Where are the knock sensors and cam sensor?
Within the same generation it's a direct swap