josh4ku

iTrader: (10)

I am installing a meling oil pump into a 5.3 engine. The pick up tube came out of a 2001 ls1. It came with a black and green o ring. .

KCS

iTrader: (20)

It should have come with instructions as to which one to use too.

gMAG

iTrader: (1)

The Melling I bought came with 1 black, and 1 green ring.
I used the green (larger) one with success, even though a blue one (smaller than the green) would have worked.
The black one has the smallest girth to it, if I remember correctly.

WE TODD DID

iTrader: (2)

Use the one that fits good. Not too hard to figure out. I'd trust my own judgment with fitment of the parts in my hands before I trusted someone on the internet.

josh4ku

iTrader: (10)

Well both fit, which is why I was stumped ended up talking to my engine builder Thompson motorsports and they use the green so that's the plan!