Anyway to tell a 4.8 from a 5.3 LS?

[4EyedTurd]

Are there anything that will tell a 4.8 from a 5.3ls? Motor is supposed to be a 2000 model from a truck

[dee]

Casting numbers.

[BP]

5.3s have dished pistons, 4.8s are flat. You can tell the difference through the spark plug hole.

[Sleeper]

something on the back of the motor too i think.

[fastwhite99gt]

Blocks just say 4.8/5.3 on them. The 6.0 blocks have that cast into them. You have to check the pistons on an old one like that. Some of the newer 5.3's have flat top pistons, so you would have to pull the pan and check the crank and rods to be sure.

[cool cat]

Hot Rod Magazine recently did an article about the very subject. I'm sure its on their website somewhere.

[racrguy]

Why not pour a cylinder?

[mystic96]

Hot Rod Magazine recently did an article about the very subject. I'm sure its on their website somewhere.

I searched through their site real quick and didn't see anything, but I've got the magazine here

It's difficult to identify the 5.3l and 4.8l because the blocks are the same; the difference is inside. The 4.8L uses an 83mm stroke and the 5.3L's is 92mm (the same stroke as a 5.7L, 6.0, and 6.2L). So how do you easily sort out the two displacements?

If you can get a peek at the top of the pistons, either by pulling a head or by getting a bore scope in through a spark plug hole, you'll have a shot at determining the displacement. If you see dished pistons, congrats--you've found yourself a 5.3L. If you see flat top pistons you've got yourself a garden variety 4.8L or higher output Gen IV 5.3L. Time to check the crank. If you see casting number 12553482, you've got a 4.8L. The 5.3L should have the same crank casting number as other 3.62-stroke LS engines -- 12552216.

[naynay]

Doesn't matter one way or another

[MattB]

If it's still in the truck, or the truck is readily available, look at the emissions decal.

[BP]

Get a big balloon and stick it over the tailpipe and spin the engine 4 revolutions. If it fills with 5.3L of air it's a 5.3, if only 4.8 then it's a 4.8.

[cool cat]

lmao

[Baron Von Crowder]

If it's still in the truck, or the truck is readily available, look at the emissions decal.

Or grab the 8th digit of the VIN.

[JimD]

get a big balloon and stick it over the tailpipe and spin the engine 4 revolutions. If it fills with 5.3l of air it's a 5.3, if only 4.8 then it's a 4.8.

lol

[85turbocoupe]

If the accesories are off on the front of the block it says 4.8/5.3. There's a paint mark that tells which it is.

http://imageshack.us/a/img854/6766/g0c1.jpg