Which engine oil is best for pulling 55 tons gross on a cummins isx?

Lots of variables there. I'd say pulling those loads 20k miles on dino oil, 40k on synthetic.

Synthetics definitely have advantages. May or may not be worth it. If I went synthetic, I wouldn't use a blend

 

I'm Driving a 2012 isx.

Delo400 non synthetic is what it likes.

Motor is quiet and oil consumption is the least. It currently has a leak. Delo slows it down considerably.

Another company I see occasionally. Uses Rotella. Their motors aren't very quiet.

Don't even think about using mobil. The motor will sound like a tank ready to blow up.

 

Everyone uses different oils.
Got a 2010 isx and sold a 2013 isx with 960k miles, used rotella with a gallon of Lucas it’s entire life, nonsythetic

 

Some people swear by Lucas, some swear at Lucas.

 

And everyone wanted his 30-30 Winchester

 

This is the one I wanted!

Mare’s Leg | Henry Repeating Arms

It was made for him by his friend Von Dutch.

 

Um,,,wrong Lucas,,,he was gay, you know,,
I used Rotella T 15-40 in my Big Cams and never had a problem.

 

I don’t care who he was banging, still had a mean rifle,. though didn’t he and Angie Dickinson make a porn movie...