Our Wal-Mart has Rotella T6 5w40 oil for 19.50 a gallon. Any opinions on this oil? I can't get Mobil1 5w40 locally and thought the Rotella might be a good replacement.
The Rotella 5W-40 is a ACEA E9 and SM/SL rated oil and from what I can find does have good ZDDP levels. From what I've read its a really good oil and wouldn't hesitate to run it if Mobil One 5W-40 wasn't available.
The below oils are acceptable for the 4.0 and prevent the gear wear IMHO.
Mobil One 5W-40 "Turbo diesel truck" Good for all around weather.
Rotella T6 5W-40 Also good for all around weather.
Mobil One 0W-40 For freeze your nibbs off kinda cold.
Mobil One 10W-30 High Mileage SL rated also going all around oil.
If you live in a place where none of the above are availbe then a ACEA rated oil is OK but not preferred.
Once again all this is just my opinion unless you happen to share it then it becomes our opinion such as then I cannot call it my opinion and I don't know what I think about someone taking my opinion.
Here is where someone did an analysis of a virgin sample of 5W-40 Rotella T6. The levels of ZDDP (Zinc and Phos) where very high). It also has a Total Base Number (TBN) of 11.7 which means it has a very robust detergent package in it.
Honestly for the price of $20 bucks a gallon I think its a pretty good deal and maybe try it next oil change.