is it okay to use 0w40 synthetic year round?? The reason I ask is I have an abundance of it that i got free through work. it gets up to 100*F in the summer and i'm wondering if it'll be to thin. It is Esso XD 3 and is CJ4 rated. Would it be okay to mix it with a gallon on 15w40?

 

I don't think 0W-40 will be a good selection for the summer. The latest viscosity chart I have seen indicates that this weight should only be used up to 50 deg F.

 

that's what I dont get, shouldn't 0w40 be exactly the same as 15w40 when its hot?

 

I was thinking the same thing unless it has some sort of additive package for extreme cold weather.

 

0w40, 5w40, 15w40, all the same when hot, so long as its a CJ4 API rating, you have no worries. My brothers 04 6.0 has been running it for 160,000+ miles, never an injector issue, never a problem. I am running 5w40 Delo and am at 60,000 miles. Fords rating chart doesnt have it rated. Its really for cold starting and preventing injector stiction issues its most valuable. You are still getting the protection of a 40 weight oil for towing or extreme summer temperatures.

 

I've done it.

 

Where are you getting 0w-40 with a CJ-4 rating?

All I have seen are Rotella T5 SB 0w-40 with a CF-4, CF rating:

http://www-static.shell.com/static/c...cants/1-54.pdf


on the other hand, Rotella T6 5W-40 has a much better spec:

CI-4 Plus, CI, CH, etc.




- Shell Rotella T6 Full Synthetic

 

I thought the T-6 had a CJ rating?

 

[QUOTE=gearloose1;8666374]Where are you getting 0w-40 with a CJ-4 rating?

All I have seen are Rotella T5 SB 0w-40 with a CF-4, CF rating:

http://www-static.shell.com/static/c...cants/1-54.pdf


on the other hand, Rotella T6 5W-40 has a much better spec:

CI-4 Plus, CI, CH, etc.


I stand corrected, it is CI-4, Esso XD 3 extra. Why does ford recommend 15w40 in the summer and in the winter when towing, wouldn't 0w40 be the same, towing or not?

 

I stand corrected, if I can find Amsoil and can verify the API rating, I would consider it. The ford spec rating for oil use, is for Dino weights only, they dont rate synthetic oils, and it is for CI-4+ in my 2005. The CJ4 I am using is the ashless spec for the same oil used in 2008 and up. My issue is finding the oil I want around here. I have to go to commercial Chevron to get mine. All the local supply shops want an arm and two legs for the syn, they rarely have the same stuff twice in a row, so thats why am using Delo 400 5w40 syn. I can get it, and its working well.

 

The starting number is when it is cold, and the ending is when it is hot. The cold number is better lower for the same reason the world switched from 40W to 10W40, start ups are easer and less aggressive by the thick oil.

0,5,10,15W40 are all the same viscosity at the hot temps because they all end in ##W40

The 0,5W40 oils are better oils because it is harder to make them thinner at the lower temps and control the viscosity change.

college

 

I will add my 2 cents, I have been running xd3 0-40 for several diesels all year round, the lastest is a 2007 outlaw with 310500 km, I pull a 30 ft 5th wheel with a boat on behind in the summer time without any heating issues. I would recommend you get an edge gauge system so you can see all the engine and tranny temps. Don't ever worry about using xd3 0-40 syn , 12000km change intervals
Don

 

it is the ending number that counts