gc in 97 grand am 3.1L loud knocking

[mopar400]

I had a slight knock when cold and a little at idle sometimes but only noticable with the hood open. Well i tried gc to see if that would help at all but instead it made things worse. Now i can hear the knocking when im at a stoplight, it almost sounds like a diesel.

Im guessing i need to go to a lighter weight oil, I was using 10w30 M1.

 

[Patman]

Oil won't help that piston slap. I bought a 94 Grand Am GT brand new in 94, with the 3.1 and actually traded the car in the next year on a new 95 Trans Am well before my lease was up, because I couldn't stand that nasty piston slap! Dealer said it was normal, I said, well then I don't want the car!