10W30 in the X15 ?

[Waterloo]

(05-11-2018 )Brock Wrote:  If you look at the Cummins approved oils, 15w40 will be in there for that engine I'm sure.

The biggest reason why these engine manufacturers are using 10w30 oils is 100% because they need to meet EPA regulations for fuel mileage as well as oil change intervals and has nothing to do with it being good for the motor.

10w30 does not put less soot or ash through the emissions system then a 15w40. ... the viscosity has nothing to do with it, the reason people think that is because 10w30 is a semi synthetic/synthetic blend etc. If you compare a 15w40 synthetic you'd be in the same ballpark.

And then we have the internal damage these lighter oils cause, cam shafts do not play well with these low viscosity oils. Plenty of evidence for that, and one of the reasons many of us use the gear oil. These are now throw away motors, something most of us cannot afford. Criminal in my book.