40w to 30w

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hi everyone i have been a visitor here for years interested in oil info.
i have been driving a diesel pu truck for around 25 years (dodge,ford,gm) and used xxx brand of 15w40 and tried 5w40 in the winter in new england.
currently i have a ford 2013 6.7 with 22000 miles bought new using a 15/40 now.
thinking of running delo xle 10w30 walmart started carrying, the truck is just a commuter for me no hauling. going to switch next oil change and send a sample to blackstone.
going to take the plung and switch to the 30w after all the years seams tuff lol.

thanks brian....
 
If the manual allows the HDEO 10w30 that meets the specs and you don't tow then it should be fine. Make sure any 10w30 you use meets warranty requirements.
 
Originally Posted By: dieselguy67
hi everyone i have been a visitor here for years interested in oil info.
i have been driving a diesel pu truck for around 25 years (dodge,ford,gm) and used xxx brand of 15w40 and tried 5w40 in the winter in new england.
currently i have a ford 2013 6.7 with 22000 miles bought new using a 15/40 now.
thinking of running delo xle 10w30 walmart started carrying, the truck is just a commuter for me no hauling. going to switch next oil change and send a sample to blackstone.
going to take the plung and switch to the 30w after all the years seams tuff lol.

thanks brian....


10w-30 is what ford specs now for non-towing situations. Must be nice to find the delo 10w-30. Ive been looking for it for a whole year now.
mad.gif
 
it just showed up last week, gallon jugs and quarts....
all so ford oil filters for the 6.7 diesel!
 
Originally Posted By: dieselguy67
it just showed up last week, gallon jugs and quarts....
all so ford oil filters for the 6.7 diesel!

Cool Ima keep looking! But your ford is spec'ed for 10w-30 if youre not towing or hauling. Im sure its a hard pill for you to swallow if youve been using a 15w-40. Id be freakin out a lil myself.
 
Originally Posted By: ARCOgraphite
Is that engine spec'd for 30 GRADE in warm ambient temp? You have a 100K warranty on that IIRC.



Ambient temp is largely irrelevant. It's not air cooled.
 
Originally Posted By: dparm
Originally Posted By: ARCOgraphite
Is that engine spec'd for 30 GRADE in warm ambient temp? You have a 100K warranty on that IIRC.



Ambient temp is largely irrelevant. It's not air cooled.


True dat!

I've not yet collected much data on the new 6.7L PSD, so I'll reserve comments specific to its wear trends.

But I can express with clear distinction and proof that, as a generalization, other PSDs and Dmaxs and ISBs don't change their wear trending when a thinner approved fluid is used. I absolutely hammered my Dmax a few summers ago with dino 10w-30 through the Rocky moutains pulling my heavy travel-trailer, and going deep into the desert southwest in June/July, and running as low on the dipstick as I could safely run, all to see just how brutal real use could be and how a dino could hold up. My UOA came back completely normal and fine and would have been suitable for continued use! Posted here at the time for all to see.
 
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Ford must be serious about recommending 10w30 CJ-4, because at all my local Wal-Mart stores, there is Motorcraft brand 10w30 CJ-4.

The back of the bottle says Ford recommends Motorcraft 0w30 HDEO in 0f or below. I only have seen that in some specialty auto parts stores. That would probably be a big advantage during winter in New England.

I know some habits are hard to break. My father used 10w30 in every gasoline engine in my family, except in a few situations. He used it even in multiple cars that would say "5w30 for all temperatures, 10w30 allowed in certain higher ambient temperatures." I followed that until around 2003.
 
Originally Posted By: dparm
Originally Posted By: ARCOgraphite
Is that engine spec'd for 30 GRADE in warm ambient temp? You have a 100K warranty on that IIRC.



Ambient temp is largely irrelevant. It's not air cooled.
I was thinking about -40C operation with a large oil to air cooler it would be ambient relevant. But it is true that I do not own one of these trucks or know if it has a large oil cooler. Aggree with NO installed Oil cooler it would not be relevant.
 
The air does provide a significant measure of cooling with the air flow over the outside of the engine block, valve covers, and oil pan.

Other things remaining equal, higher viscosity oil has higher film strength. Other things never remain equal. If the engine maker increases the surface area of the bearings, then there is less load per unit of area and lighter viscosity oil can do the job fine. Or, testing shows that the bearing surface area is sufficient in the first place for the lighter oil. A very large diesel engine that puts out 7,000 hp per cylinder uses 30 wt crankcase oil. A big jet engine that puts out 90,000 hp uses 5 wt. Expect to see 5W-30 HDEO become the standard in the future.
 
Detroit Diesel factory fills their 15L on highway diesel engines with 10w30 now, and any 10w30 or 5w30 that meets their 93K218 spec is good for 50,000 mile OCI's per the manufacturer. Not that is not a typo... 50,000 mile OCI's per the manufacturer. And it has nothing to do with towing or not like one post said. These truck are regularly pulling GCVW upwards of 80,000 lb and even more is some cases, over mountains, thru deserts, thru Canadian cold, etc. All temps, all locations throughout N. America. And TransAm trucking of Olathe, KS, just moved their entire fleet, mostly KW trucks with Cummins ISX or Paccar engines over to 10w30 exclusively. Schaeffer is their supplier now.

The PC-11 diesel oil standard that is being developed now to go beyond CJ-4 will most likely be a 30w spec with NO allowance for using 40w oils. It is already out that the PC-11 spec will NOT be backward compatible.

And most diesel engine oil coolers are oil to coolant anymore. Hardly any major diesel is using oil to air cooling methods.

For the OP, if the OEM allows for using 10w30, the oil you choose meets their specs, then go for it. This thicker is better hold over from days gone by is not always the best solution today.
 
Ok just did the oil and filter change. 13 quarts of Delo XLE 10w30.
I will probably go to 25% left on the OLM
I will sample and post the results.

Thanks guys!!!
 
I have used 5w30 and 5w40 in my Pathfinder.

Can't say i have noticed any difference.

Did get a very small improvement when i went from A3/B3/B4/C3 to A5/B5. But it was tiny.

Oci is due now as just turned 120k so 5k since last one.

If it is within the specs of the engine i don't think tbere is a wrong choice
 
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