Personally I don't think royal purple is any better than mobile 1. I do think amsoil is better but as far as how we use these trucks mobile 1 is by far the best value. Go to wal-mart and pick up a 5qt jug for like $29 and get a good filter.

don't know about everyone else, but even if I was using an oil rated for a longer change cycle (using castrol right now) I still would change it at 3,000miles religiously as I do now. That might just be me being ocd though

+1 on the mobil 1 EP

I use amsoil and go 7-10k on my changes, but I buy the 25k intervel amsoil. Now I got grilled last time I posted this by hydra and shrps (no hard feelings guys I know how passionate and ocd you guys are about maintenance) so I'm gonna take their advice have it tested by blackstone labs next time just to see how much life is left or if it is living on borrowed time (hopefully it has life left).......................

keep us posted, it'll be interesting to know how well the oil is still working over time.

What do u mean have it tested by blackstone labs next time?

I think he means having it tested to see how well the chemical structure is holding up and how well its lubricating the engine. You know making sure its still doing oil stuff

oh, have the oil tested lol, I was like oh oh oh I want my engine tested too lol

Mobil1 EP it is....Been off reading others threads about M1 and think I'll give it the go across the board...

Now about that "Good Filter"

NAPA Gold
Purolator PureONE
K&N
Other?

One of my other trucks engine has 200,000 miles been running mobil 1 from day 1 i missed an oil change let the oil go for 20,000 still had gold color to it that was my test lol and it still runs it has the I6 and will smoke the 33 on it