what is a good recommended oil brand

Allot of the major brands are just fine these days. I use Delo XLE 15W-40.

 

I have a new dd13 I used rottella 10W30 & not using additives ( have no plans to at all). My Uncle did testing on engine oil at the oil refinery. No need for adding any thing to the oil. I'll stick with the science. I don't idle either.

 

t5 is better. thinner the better. starts nice in the winter. 10w means the air temp is above freezing. 5w means below. 30w is the weight.

 

I go with what my book recomends for the engine weight wise and then use rotella semi-synthetic late spring-fall and full synthetic late fall-early spring out of habbit. Pretty much any national brand will be as good as any other within a small margin of error with the top shelf stuff obvious being a tad better. Mobile one is also good if you want a more "premium" oil

Also i would throw half a bottle of lucas in there every 3rd or 4th change to help clean the stuff out. Ive found it does tend to degunk the engine a bit better and you shouldn't need a full bottle if everything runs fine. But thats just MY opinion.

 

i have tested Delo, Rotella, Delvac on DD15
Rotella is winner because less fumes are coming from breather, less oil is getting out from rear of engine. We all know that every DD15 is leaking form behind )))
If you put Delo in it you will see many leaks on engine, Delvac is in the middle of Rotella and Delo.

 

When I had a little blow by, I switched to Guardol ECT, and the blow by stop on my former Cat. I now use a similar oil from a local distributor with similar additives and some.

 

expensive?

 

Delvac 15-40 CK-4 for the win.

 

Cemex uses Chevron Delo 15-40 CK-4 in their mixers, and haul trucks.

And nothing, no engine, will ever get run harder than those mixers.