geo1rem

How can I tell the difference by looking at the motor? I see on the back of the LS motor 4.8/5.3.

If you dont mind PM me that would be great. I do not come to this site very often.

Thanks George

VATOCLOWN

mine has a yellow paint mark over the 5.3 side of the stamp on the front under the water pump

omar2guy

Yea usually they have a paint park on which ever one but I would look through the spark plug hole on the heads and take a flashlight , if they are flat top pistons u sir have urself a 4.8. If they have a little dish to them its a 5.3

86_irocz-28

iTrader: (5)

^What he said^

X-Bomb Racing

iTrader: (1)

I took a grinder to the 4.8 on my block. But yeah mine had a yellow dot on the 5.3

Blackpanther99

iTrader: (8)

Same on mine^ Yellow marking.

sjuliani

arent the 4.8 drive by wire?

y2k_ta

iTrader: (80)

Nope, not from the factory. My '99 Silverado with the 4.8L is cable driven.

2000PewterT/A

My 04 4.8 Tahoe is DBW from the factory.

sschevy86

I have a Alu 5.3 with casting number 12572733 can anyone tell me about this engine or where to find out about it none of the sites have this casting number

y2k_ta

iTrader: (80)

Thanks for the info. I didn't know that.

Mt.Dew

iTrader: (1)

Aluminum 5.3's are the High Output version. 10 to 1 compression, 243 or 799 heads. Not as common as the Iron block version. What year is your truck? That will nail down what generation it is.

Mt.Dew

iTrader: (1)

Oh, In case it's not in a truck. The L33 (earlier) won't have a cam sensor on the front cover. the LH6 and LC9(later) will. LH6 's came in Trailblazers and Envoys. LC9 came in Silverados.
LH6 and LC9 engines also had Active fuel management.

IRNMADN

I pulled a 42K mile LM7 (iron block 5.3L) out of an 04' Yukon XL. I had to verify what motor it was by the VIN. Mine had no paint marks indicating it was a 4.8 or 5.3. The motor was very clean as it was low mileage so don't think it wore off or anything. I pulled it apart to upgrade and clean to verify it has the dished pistons (which I'm swapping for a set of 4.8 pistons). It also has a DBW TB, not cable driven.