I run the 15W-40 Amsoil in my Duramax and this week even when it got to -10ｰ overnight I never plugged it in and it started the same as 40ｰ. Takes longer to warm up obviously but it's no where near the 6.2 I had years ago
I am impressed with the truck and the oil.
BTW Rotella 5W-40 Syn. is a Group 3 hydro processed oil whereas the Delvac 1 and Amsoil are PAO base. That is the reason for the jump in price if you compare.
I am impressed with the truck and the oil.BTW Rotella 5W-40 Syn. is a Group 3 hydro processed oil whereas the Delvac 1 and Amsoil are PAO base. That is the reason for the jump in price if you compare.