Hi all, haven't been around in a long while, but i'm in need of a quick answer. Will the 5.9 be alright with regular 10-30w oil? It's 0 degrees out and i'm paranoid to start my truck up and run it with 15-40.
Also, will regular oil be ok? In the owners manual it says somthing about using an oil with specific ash weight in it? I don't know what they mean by that.
Anyone?
Thanks

 

5w/40 is what you want. Gotta be diesel spec, CI4+ or better. Car oil doesn't have the dispersants and anti-coagulants necessary to handle diesel soot.

 

Cool. I'll see what i can find.
Thanks
Brent

 

Wally world should have it.

 

Rotella 15W-40 is what I use. That and Lucas Oil Stabilizer.

 

Ive been running 5w-30 amsoil in mine. I love it.

 

Use either 5 W40 or 0W40, in the winter. (I use 0W40 all year round) At 100c (operating oil temp) 0W40, 5W40 and 15W40 have the same viscosity. Pour point is much different; 15w40; around 0c-32f, 5 or 0W pours at around -40c or f. Oil does nothing if you can't pump it were it is needed!

 

I use 10W-30 when the weather gets cold, been doing it since the truck was new, no problems. Makes the truck easier to start.

If I were going to work the truck really hard though,
I might keep the 15W-40 and use the block heater instead.

 

Shell makes Rotella T in a 10W-30, Cummins says it's OK as long as the outside temp will be 10 degrees F or lower.

Don't run non-diesel oil except in an emergency, it cannot hold the soot.

 

Thanks for the replies. I've been looking around today and have seen a few different oils. Is the 0-40 and 5-40 only available in synthetic? I can't find any regular dino oil in anything lower than 15-40 (what's in the case now) unless i go to 10-30. I think i might have seen 10-40 somewhere, but that's not much better than what i've got now.
Main reason i want to put in a thinner oil is it's 4 degrees at the highest right now. Even when it's in the 30's the truck makes cringe every time i start it. Jump in, cycle the heater grid a couple times and start it. Starts right up, but the oil pressure gauge doesn't even move for 5-10 seconds. I don't like that much.
So it looks like i'm about to spend 65 bucks on an oil change!
Thanks

 

I've been running 10w30 RP for about 17 years now. It's not even the diesel grade lol. No internal problems yet. I would use the diesel stuff but I use what's free to me. My dad keeps a 55g barrel in the garage for all the other cars. Always high quality filters though (ScAmsoil at the moment).

 

15w40 Amsoil Diesel Oil and plug in the block heater. Synthetic doesn't thickin up like dino crap so don't let the 15 weight scare you, although if you want a 5w30 diesel oil, Amsoil makes that too. Their 15w40 remains fluid down to -44°F.

http://www.amsoil.com/a/Synthetic-Di...Oil-Engine-Oil

I live in Manitoba, Canada and guys I know run the 15w40 Amsoil year round no problem. $65? I don't see that as a problem. We have guys running the 15w40 for over a year between changes. When you factor in the longer drain intervals with a high quality synthetic, the price point is actually not bad at all.

Nik

 

i dont know if its the best but i run 15-50 synthetic mobile one in my trucks have been for years. not real cold around here.

 

That's just the lousy stock gauge. You have 65-70 psi within 2 seconds.

 

65 Dollars doesnt go very far when it comes time to rebuild it. A high quality oil is well worth the money in my opinion.