2000chevysilverado

iTrader: (11)

I wouldn't have changed the ring if it didnt need it I would get one straight from gm and start there

1994Vmax

iTrader: (4)

It sounds like LY6 did before it blew up honestly. And it ticked rattled and made all kinds of wonderful sounds with a notable loss in oil pressure. One of it's LS7's fell apart and ate a lobe off the cam..... I would throw those lifters in the garbage personally and use something, hell anything else.

I don't think it's your o-ring as that would be an upstream loss and you would cavitate the pump. But I guess you never know.

SlickSierra

iTrader: (4)

https://ls1tech.com/forums/generatio...mp-o-ring.html

AUTOT3K

iTrader: (3)

So you think its the o ring?

AUTOT3K

iTrader: (3)

I'd rather not have to pull the heads again. And would the lifters really fail that soon? Barely even 250km and maybe 4 hours of run time

SlickSierra

iTrader: (4)

Hard to say, could be many things but its something to look at. I got a new oring from the dealership that was blue and it didnt fit at all. I grabbed the one out of my vic reinz gasket kit and was red, fit nice and tight.

AUTOT3K

iTrader: (3)

Fml haha
So the o ring must hold at idle then leak at wot. Causing lifter starvation...then noise.

1994Vmax

iTrader: (4)

Possible but you are still seeing a steady 40 psi of pressure to the engine at least according to the gauge. Try the o-ring first I guess as it is by far the cheapest option. However the o-ring is upstream of the pump and doesn't see pressure..... it's on the suction side, it can't. Now that's not to say with the idle rpm and lower volume the loss is not great enough to do anything but once demand increases with rpm the leak starts to allow cavitatation. But that is a long shot.

AUTOT3K

iTrader: (3)

That's true. I'm gonna call gm tomorrow and see what they list off my vin for a seal number.

Id replace it by dropping the pan completely from the truck. Then I can see the filter on the pickup tube too

1994Vmax

iTrader: (4)

Not a terrible idea.... and I keep forgetting you are a 2wd so dropping the pan is a bit simpler, lol. It would be good if that fixes your problem! Then you get some more vids and hopefully not have the CPS ruin it for you, lol.