synthetic 15w40

[murse72]

looking for diesel motor oil synthetic 15w40 all i can find is royal purple in synthetic in that weight. anyone ever ran their diesel oil ?

 

[clemsonfor]

I will reply to this one just like the other post?

Why not use a better product or oil that will flow better for cold startups and use a 5w40 synthetic? There are several of those on the market and on walmart shelves. This is the benefit to syn oils, they allow and flow better cold but retain their viscosity better at operating temps to maintain their 40weight designation.

 

[murse72]

well my owners manuel does not list that weight. it list 30 10w30 or 15w40. not 5w40

 

[mkreitler]

5W-40 is the most common weight in synthetic oil for diesels starting at the end of this year there is going to be a whole new breed of diesel oils.....stay tuned in!!!

 

[Soundguy]

well my owners manuel does not list that weight. it list 30 10w30 or 15w40. not 5w40

engines that spec 15w40 can run on 5w40

 

[clemsonfor]

well my owners manuel does not list that weight. it list 30 10w30 or 15w40. not 5w40

5w40 is thicker than 5w30. 5w40 is just at thick as 15w40....except at cooler (not operating) temperature the 5w will flow better thus flow more oil to the bearing and valve train on a cold start up. All oil thins out as it warms up to 200F or so when its at operating temp, just how much depends on what weight oil it is. 5w40 and 15w40 are both 40 weight oils thus once warmed will perform identical, when cold the 5w out performs the 15w.

 

[dickfoster]

What they said. What I'm running in my tractor. Valvoline™ Premium Blue Extreme™ Diesel Engine Oil: Heavy Duty Products - Valvoline(R)

 

[Gary Fowler]

5w40 is thicker than 5w30. 5w40 is just at thick as 15w40....except at cooler (not operating) temperature the 5w will flow better thus flow more oil to the bearing and valve train on a cold start up. All oil thins out as it warms up to 200F or so when its at operating temp, just how much depends on what weight oil it is. 5w40 and 15w40 are both 40 weight oils thus once warmed will perform identical, when cold the 5w out performs the 15w.

This explains it well. Sometimes the OEM manuals are so out of date that what is specified in them is no longer available. As for 15W40, my Walmart usually carries Shell Rotella T6 full synthetic in several xxW40 grades. Get the one you want but the lower the W number the better it will function in cold weather. In hot or full operation temps, there will be no differences.

For West Monroe, La. you really wont need the 5W or 10W for cold weather since it rarely gets below freezing, but if it is the same price, why not go for the 10W40 or even 5W40? Check the Walmart closest to you and look at the Shell ROTELLA T6 (full synthetic) for optimum performance or the Shell Rotella T (no 6 on it) which is standard dino oil and will be much cheaper if you want to go that route. I think you will find 15W40 in both types.
I use the Shell Rotella T6 in everything I own, lawnmower, tractors, cars, motorcycles, 4 cycle boat engines etc. In my boat I noticed that I get about 200 RPM more using full synthetic oil compared to regular oil of the same weight.

 

[mddorange]

This is what I always use, Rotella-T6 synthetic 5W-40, and have been very happy with it.

 

[murse72]

i have not found any synthetic in 15w40 anywhere locally walmart autozone advance auto and o'reilly that is why i posted the question. and royal purple is the only synthetic in 15w40 i found online