Which oil for 2003 Silverado 6.0L?

[CleanSump]

I was considering a ow for the winter cold starts. It starts up fine due to being fully winterized but is pretty chattery at first (seems like lifters) then quiets down. Was thinking ow might help prevent minor wear since it has better cold flow.

You can give it a try. It won't hurt anything. -40F is down there where 0W-30 might chatter less. I'd still use either HPL EC 30 or the Valvoline Restore & Protect to see if the lifter chatter goes away with some cleaning. HPL EC 30 eliminated my BMW startup lifter chatter in just 100 or 200 miles. It doesn't usually get below the teens here, though we do get occasional drops to single digits. Not Artic conditions like you have.

 

[heavy260]

I was considering a ow for the winter cold starts. It starts up fine due to being fully winterized but is pretty chattery at first (seems like lifters) then quiets down. Was thinking ow might help prevent minor wear since it has better cold flow.

I’ve used M1 0W-40 in my 2011 6.0 for a little over 2 years and my lifter noise has gone away. I tow heavy (beyond ratings of the truck) about every other weekend from May through October and my oil doesn’t look black anymore like PP 5w30 did. I’ll be cutting my filter open soon just to see if there’s any crud in the pleats. The M1 hasn’t been at Walmart consistently so I grabbed Castrol Euro 5w40 for now but as soon as I see the M1 back I’m stocking up.

One thing I did this past winter is I did not start my truck when it was -15 or colder. I just waited until overnight temps came up and then started it. I figured if I really needed to go anywhere I’d plug it in first. I put the wear and tear on the Vibe instead.