Travis_

Sorry to bring this up I searched didn't find anything but I also only looked on the first page lol... Like it says who is running it during the summer? Around here it gets 100+ Local Walmart has the Rotella syn but the bottle says superior winter protection. I am not to sure if synthetic is ok to use during the summers. Still new to the diesel thing.

Roperteacher

Hey Travis, I am just north of you in Hemet. I am down that way all the time roping etc. I run the AMSOIL 15/40 Synthetic in my truck year round. Thats my suggestion.

rjm022

synthetic is an excellent oil for year round use- just remember- rotella is a group 3 synthetic- not a group 4 like amsoil or mobil 1. redline oil is a group 5.

D45

I use Amsoil Heavy Duty Diesel & Marine 15W-40 year round.........

dozer12216

Syn if fine in summer also. Any good quality oil that meets service requirments of engine will do job. The higher price of some oil gives more bragging rights, but not much else IMHO. God , I love a good oil bragging discussion. A passing EOA is sufficent bragging rights for reasonable people.

Travis_

Were you in the last rodeo down here?

D-Roc

Just because an oil is Group IV or V over a group III, doesn't mean it is better...I know a few Group III's that rate quite high. Perform UOA to find what works best for your setup, instead of taking someone's opinion at face value.

rjm022

i have the amsoil single bypass set up on my truck and i use amsoil 15w-40 oil. i routinely get 20,000 miles out of my oil. my oil analysis says i could go longer- but i change it at 20,000 miles.