Hello all,

I have a silverado which I installed an ls1 out of a c5 vette. I have a lifter pecking pretty loud. I have penzoil 5w30 in it now, I am assuming that the engine originally had the mobil one synthetic package. Could this be my problem? Do I need to go back to synthetic oil or maybe switch to 10w30. All your help is needed.

thanks alot,
Jarrod