Hello, so my 2007 Chevy suburban 5.3 has some valve train noise that doesn’t seem like the typical lifter knock. Aside from some short lived piston slap, noise I’m asking about today pertains to a more of a click. Like an old style push rod engine. It’s largely happening at a cold start and under load. It goes away after a while but I’m worried about the damaging effects that are ensuing with this. Could it be that I need a valve lash adjustment? Maybe run some ATF though? Or is it something more serious?

Thanks for you time

 

How many miles on it?

 

its has 187,000

 

AFM lifter issues can occur as the miles pile on. Known issue on AFM 5.3 motors. Google it up.