I noticed the same monster, but I'll likely keep running the 5w-40. I think the 15w-40 Rotella is just a really really good non-synthetic. I tried Valvoline premium blue (non-synthetic version) in 15w-40 and immediately my truck ran worse. I never used it again. I've heard the synthetic Valvoline 5w-40 is really good though. I see the Rotella everywhere though so that's what I run. I even run the T6 in my TDI as well.

 

Mdub, I agree i am not switching back either. I ran valvoline blue in my cummins and it ran well, but won't put it in my stroke. It was 0* here in Ohio last week and the truck started after 3 cranks and the truck was unplugged. I have had the truck 7 months now.. And I'm lovin it.

 

Mdub707 is the man with the know, when it comes to the six-oh!

 

bluecoon, do you have a way to moniter your oil and coolant temps?

 

Yes Mdub is definetly the man with the know.
No Robo02, I don't currently have a way to measure the oil and coolant temps. I plan to get a SCT Livewire to monitor them within the next couple months though.

 

Ok, then you can determine the condition of oil cooler, if no problems, a coolant filter and you might be able to change from Ford coolant without the chemical flushes. Time consuming but fairly inexpensive.

 

Sorry for no updates guys. I haven't been able to do anything to the truck due to the rain and lack of funds. I will repost as soon as I'm able to get some more done to the truck. Thanks for the replies, they're greatly appreciated!!