Originally Posted By: Roadtrash
I own an '09 Silverado with the 5.3 with AFM. The manual stipulates the use of 5w-30 in order for the AFM to function properly. I drained the FF at 1k and am now running M1 5w-30 with a M1 filter. I have 6k on the truck now.
Is it ok to run the German Castrol 0w-30 in this motor? I have read reports that it's a bit thicker than M1 5-30...so not sure if the AFM will function properly? I live in NH, and we get pretty cold winters up here.
I am still reading up on old posts about GC 0w-30...but would appreciate any help.
Thanks!
You certainly can run 0W-30 and be fine( with AFM and in general ). However, there is no real need IMO. I live in NH as well. Had a 2005 Silverado and a 2007 Silverado( new body style like yours )both with the 5.3L( 07 had AFM ). I ran 5W-30 year round with no issues.
I ran Royal Purple synthetic oil but the point is a 5W-30 synthetic will flow just fine at the temps we see here in NH even in the dead of winter. You can run the 0W but if you are running a synthetic a 5W will be fine year round.
If you want to run a 0W and you like Mobil then as the other guy said why not run the Mobil 1 0W-30? Available cheap at Wal-Mart. Lots of guys on the Chevy truck forums run Penzoil Platinum 5W-30 year round from this neck of the woods and even Canada with good results as another option for you.
Note - GM's Active Fuel Management(AFM) system seems to be a little more forgiving than Chrysler's Multiple Displacement System(MDS) that calls for 5W-20. I wouldn't run a 20W-50 but anything 0W-30 - 10W-30 seems to be fine. Some guys even talked about running 10W-40 and having the V4 indicator light come on in the DIC which indicates AFM is active.
Enjoy the truck.
This was mine...