I don't want to start a war but I need to change oil. Any oil recommendations?  I've been using full synthetic amsoil for the last 3 changes. But wondering if there's a better option. 

You can read in here for days

http://www.bobistheoilguy.com/forums/ubbthreads.php/forums/52/1/Passenger_Car_Motor_Oil_(PCMO)

 

Personally I'd stick with the amsoil.

 

Some good info in here too.

http://forum.mopar1973man.com/index.php?/topic/10426-new-cj-4-oils-in-older-flat-tappet-engine/

Stick to what you have been using, can't go wrong there if you are running their 15w40 heavy duty and marine oil.  

Ok so thats two for Amsoil. Hmmmm you guys didn'the take the bait. Lol

Like said above, you can read for days here. Dino all my life with no problems.

rotella...

Ok so thats two for Amsoil. Hmmmm you guys didn'the take the bait. Lol

You asked if there was a better option.......................

Can't really go wrong with amsoil they make a great product I just never really cared for the price. I have run standard Rotella and the T6 synthetic with good results. It's available locally and is fairly inexpensive.

If you're running synthetic and aren't leaking oil, no need to change. I'd run amsoil if my all my seals didn't leak so bad. In all honesty, the Cummins will like just about any motor oil, rotella, valvoline, amsoil. I ran rotella t6 for a couple hundred miles and I think it quieted my motor down a smidge, but the oil pan gasket and front crank seal were leaking like a sieve so I switched back to valvoline premium blue. Don't need to overthink it too hard.

Ran so far 253k miles... Chevron Delo, Mobil Delvac, Valvoline Blue, etc. 15w-40. No issues on petroleum products.

clean oil is the best one to run that meets the oil spec requested by the engine. one that still has the additive pack after your desired run interval.

The slippery stuff.