Originally Posted By: TheFlatlander
Very interesting reccomendation. I just read up a bit on RotellaT. This oil is designed for diesel engines but is ok for gasoline as well? Stupid question but I had to ask!
How does your 4.0 perform on this oil? What filter do you use with it?
Thanks for the reply!!
Lots of people do use Rotella T in gasoline engines. Diesel engine oils (HDEOs, or Heavy Duty Engine Oils) are typically designed for longer life between changes, and have stronger detergent and acid control packages, but other than that are fine for most gasoline engines. Some of the additives might conceivably reduce the life of a catalytic convertor in 2007-up cars, but the Zinc and Phosphorous levels that Rotella T has now are actually not that different from what gasoline engine oils had back in the late 90s, maybe lower. It is, after all, SM rated as well as CJ rated, so it meets all current gasoline engine oil requirements. The only think "out of spec" for a 4.0 is the 5w40 rating, but the 4.0 responds very well to that rating and is generally believed to "like" a heavier oil. It doesn't develop excessive oil pressure or anything like that on 5w40, and I found that the oil pressure changes less as the engine warms up than it did when using a 10w30.
I've been using Purolator filters for years, and I generally go with the PureONE version. On the Jeep I run the full-size PL3001 instead of the "shorty" version that was used OEM. I like the added 1/2 quart oil capacity and the extra filter area, and the threads/gasket and other important features are identical. On my '99 Cherokee there's enough room for the long filter, if there's not on your application then go ahead and run the shorty.
The Jeep is running great on this combo so far, although it spent most of its life (previous owner) subjected to whatever [censored] oil Jiffy Lube had in its bulk dispensers. Its hard to kill a 4.0....
