Originally Posted by Vern_in_IL
Originally Posted by Snagglefoot
+1 on the 2014 GM AFM re-design. It received a variable rate oil pump system, much higher pump rate, much higher oil pressure, and re-designed lifters. There is little resemblance to the previous system. So far I haven't heard complaints on it. There should be 2014 models with 100,000 miles on them by now.
So can you run thinner oils and still maintain oil pressure?
0w20 ? Hey, it's middle grade these days !!!
I recently posted a link to the L83 engine - GM changed many things - and kept some things from the former evolutions like the stiff lower end and mains - and as a former machinist just figured they wanted to keep the larger machines capable of boring and facing the same displacement blocks - whereas the new heads might just be a new CNC set up to handle the new blank.
I have also made the comparison between my former 5.3L's that did not use the new oil pump system, did not have piston jets, did not have an oil cooler.
Having said all that - and with 2017/2018 units - I'll drive out the warranty period before I decide on the AFM delete or 5w30 oil - since both are saving me money now.