If you are still in Anchorage, check Napa. They have Premium Blue Valvoline and check their flyers since they have had it on sale in the past.

 

I don't see any reason why not.

 

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thanks Dak--going to try them this afternoon

 

Thanks--I just hit Napa! Good to go...

 

I've been running 10w-30 in my '15 since new, also in the two previous 6.0's I had. UOA every oil change with repeatable results every time, excellent, I also run until message center says "change oil now".

There is nothing wrong with a 5w-40 on the approved list, but a 10w-30 will deliver the same results in a 6.7.

 

roadrunnner01 - I have mixed feelings on 10W-30. I don't like the 10W part for Alaska. IMHO, it gets and stays too cold especially if you are parking outside overnight. It is actually NOT recommended for this weather if you look at the oil chart in your manual..

Luckily Icthus and I are both in the banana belt of AK, so more than likely it's fine - however, I like to be prepared to go to other areas in the state at any given time - and some of those areas get wicked cold. Areas around Fairbanks were -60F this year. I'm not sure I believe the Delta Junction -72F gas station thermometer, but either way, it was cold out.

I really don't want to start another oil debate... Just stating why I like at least 5W oil.

 

I was at Atwoods this morning and they had gallons and galons of Rotella T6 that is CJ-4.

 

If you're traveling to those bone chilling temps I would forget the 5w-40 and go straight to 0w-30. There isn't much difference between a 5w-40 & a 10w-30 in cold weather performance. According to the manual anything below -20f requires arctic 0w-30/0w-40.

The "W" number doesn't correlate between different viscosity, meaning, for example, a 5w-30 isn't equal to a 5w-40, or a 5w-20. Which is why its so hard for most to completely understand the SAE specs.

 

Ill bite. The 5w-30. It means at temp it will pour at a 5 weight viscosity yet maintain a 30w viscosity rating. Right?

 

I don't know much about it, but, as I understand it, the 40 will hang around and leave a layer of film on components longer than a 30 at high temps and the 5 means it will pour and flow easily when cold. A 10w will require more effort to pump but lingers a bit longer than the 5?

 

Yeah, according to the chart I should, but it's interesting that it's tough to find up here. So I just run 5w-40. For the moment, it isn't a big deal as my truck has a heated garage to overnight in. The longest it might sit in a parking lot outside is a few hours and that is rare. (and it does get bone chilling cold in that few hours)

My next oil change will be for the 'summer' so either 10w -30 or 5w-40 would work regardless and since I have 5w-40 sitting in the garage, that will be it.

 

The "W" stands for "winter" not weight and there is a different scale used for each viscosity or grade which is why a 5w-40 isn't equal to a 5w-30 or 5w-50.

 

The W rating has to do with cold temp pour points and how it pumps at as the temp drops. Next part on this "what do I need to run?" question is that depending on how the motor was designed and tested will determine what grade oil you need. All auto manufacturers operate and test their motors in a wide range of conditions and make baseline recommendations based upon their findings. After all, they have to warranty it, give ou some guidance so that if you don't follow it, they don't have to warranty it. This is also how the API Certifications come into play (i.e. CJ-4) The manufacturer usually has an operating temperature table coinciding with recommended oil viscosity for the year, model and motor you have from them - the cold (or W number) and hot (end number). So in my case, on my 2015 6.7, I look at what works for sub zero temps and summertime highs in the +70Fs. 0W is better for me than 5W, 30 is fine on the hot end. 40 still works though! However, when I lived in a warm, no snow, state 10W was way more than enough to handle our cold temps. but 40 (end number) was recommended due to the heat.

So someone saying, 10W-30 is fine for me, could very well be true for them, but not for you. Only YOU know how and under what conditions you run your truck in. The manual is their to guide you.

And I will say that the local dealers here all use 10w-30 FoMoCo diesel oil, even though, I personally believe that either a 0W or 5W should be used. (adding credence to the statement that there is nothing wrong with 10w-30) While there very well may be nothing wrong with 10W-30 in the sub-arctic - even though it goes against what the manual says, there certainly isn't anything wrong with 5w-40 either.

 

i use Amsoil. Meets Fords spec and CJ-4