pulled the 4.8.
 

Just was curious does all 4.8 always have both the 4.8/5.3 on the back of the block. I just pulled what i think to be a 4.8 but it has both 4.8 and 5.3 on the casting on the back of the block. Just a curious.

All the 4.8/5.3 have this the 6.0 just says well 6.0.

What are you doing with the 4.8L?

same bore anyway..

Nothing as far as i know probably clean it up and seal it up but no plans forit right now.

block is the same for a 4.8/5.3 thats why it says that.

Gotcha :usa:

And how can you tell if its a 4.8 or a 5.3? by the head casting number right?

by the crank. 5.3 is the same bore just a longer stroke. I guess no real way to tell unless you crack it open from my knowledge. I believe the 4.8 and 5.3 both can come with the same heads?

4.8's have flattop pistons and a shorter crank; visually that's the only way to tell, and the heads are the same. Although the L33 5.3's have flattops too I think but they're aluminum blocks.

So hypothetically speaking, if you were buying a motor from someone, and they claimed it was a 5.3. Without tearing into the motor, how could you tell if it was a 4.8 or a 5.3?