6.7 PSD why is 10W30 not approved for trailer tow

[roadrunner1]

As many have said here we use 10w-30, I cannot explain why the owners manual is worded as it is, but it is. My 6.7 is my work truck, its loaded every day, whether it be towing or having 4,000 lbs.+ in the bed, or both. I have let the UOA data confirm that 10w-30 is fine with what I'm doing.

I think the 5w-40 and not a 15w-40 recommendation is purely for fuel economy, I know these trucks aren't CAFE mandated but cold engine operation robs the most in fuel consumption.

 

[Garak]

Originally Posted By: TiredTrucker
Ford corporate gives the impression of being nuts on this, especially since heavy commercial diesels have no issues using 10w30 to move 80,000 lb of truck and cargo from sea to sea, Canada to Mexico, etc.

Agreed. Beyond that, it seems really odd that a 15w-40 isn't good for severe service, whereas 5w-40 is. The latter might be better for long drains, but for ordinary oil drains, how could a 15w-40 with the same specs as a 5w-40 not be up to the job?

I'll wager that over 50% of these trucks on severe service are getting a 15w-40, including ones serviced at the dealership.

And yes, Ford really has a giant mess going with diesel specifications. They picked a fine time to sow confusion, too.

 

[claluja]

Originally Posted By: Garak
Originally Posted By: TiredTrucker
Ford corporate gives the impression of being nuts on this, especially since heavy commercial diesels have no issues using 10w30 to move 80,000 lb of truck and cargo from sea to sea, Canada to Mexico, etc.

Agreed. Beyond that, it seems really odd that a 15w-40 isn't good for severe service, whereas 5w-40 is. The latter might be better for long drains, but for ordinary oil drains, how could a 15w-40 with the same specs as a 5w-40 not be up to the job?

I'll wager that over 50% of these trucks on severe service are getting a 15w-40, including ones serviced at the dealership.

And yes, Ford really has a giant mess going with diesel specifications. They picked a fine time to sow confusion, too.


Keep in mind that the Ford manual states that extreme cold temp operation is considered one of its severe operations.

 

[dustyroads]

I had the same thoughts as TiredTrucker at first, as my last few trucks have made peak torque way down low (1650 lb-ft at 975 rpm in my Detroit). I cruise at 1100-1200 and spend a lot of time pulling hills from 1200 down to 975 rpm. This is using 10W30 HDEO.

But when you consider the power/torque density of the pickup truck diesels, maybe it's just a consideration of the (rod and main) bearings. The pickups are packing a lot of punch in a small package, even if it is at higher rpm. Due to their size, the crank and bearing size are limited. Whereas a heavy duty diesel is afforded a bigger block, with a longer crank and massive bearings with stronger fasteners.

I would say the same for the little diesel in the Ram 1500, too. Maybe they are programming them to run low rpm, but how low can they be running?

I'm just thinking out loud. Am I way off base?

 

[Garak]

Originally Posted By: claluja
Keep in mind that the Ford manual states that extreme cold temp operation is considered one of its severe operations.

That is certainly true, but using the appropriate viscosity for climate conditions shouldn't, on its own, mean that 15w-40 is unsuitable for summer towing, or someone who knows how to use an oil pan heater or has a heated garage. If they're so concerned about every little nuance with HDEOs lately, they need to make their specification mandatory and clear. Link the spec to only E7, E9 5w-40 options with phosphorus above 1000 ppm and be done with it.

But, they have their spec on at least one 5w-30 HDEO with low phosphorus on the list, so it strikes out on viscosity and phosphorus, yet is on the list. So, you see why this gets confusing for owners.

dustyroads: I do see your point, and that's kind of what I was getting at. Now, if Ford thinks that 10w-30 HDEO has too low of an HTHS, that's fine. I may not agree, but that's not the point. If a 5w-40 is somehow more suitable for towing, I'm not sure how a 15w-40 wouldn't be, since that will likely have the highest HTHS of all the CJ-4 lubes.

 

[mbacfp]

If memory services me correct...says 10w-30 normal use...5w-40 for severe service (as defined above)...15w-40 If running Bio Diesel. Needless to say I am confused as well. I called Galphin Ford service and they said they use 10w-30 in there 6.7s they service...even the work trucks. Go figure.

 

[dustyroads]

Originally Posted By: Garak


dustyroads: I do see your point, and that's kind of what I was getting at. Now, if Ford thinks that 10w-30 HDEO has too low of an HTHS, that's fine. I may not agree, but that's not the point. If a 5w-40 is somehow more suitable for towing, I'm not sure how a 15w-40 wouldn't be, since that will likely have the highest HTHS of all the CJ-4 lubes.


Yeah the 5W40 recommendation only makes sense to me if it's for fuel economy as roadrunner suggested. If that's Ford's reasoning, why don't they say so and say that 15W is fine for a certain temperature range? I certainly would use 15W40 if I thought it was necessary to use a higher HTHS.

 

[CarbonSteel]

Originally Posted By: dustyroads
I had the same thoughts as TiredTrucker at first, as my last few trucks have made peak torque way down low (1650 lb-ft at 975 rpm in my Detroit). I cruise at 1100-1200 and spend a lot of time pulling hills from 1200 down to 975 rpm. This is using 10W30 HDEO. But when you consider the power/torque density of the pickup truck diesels, maybe it's just a consideration of the (rod and main) bearings. The pickups are packing a lot of punch in a small package, even if it is at higher rpm. Due to their size, the crank and bearing size are limited. Whereas a heavy duty diesel is afforded a bigger block, with a longer crank and massive bearings with stronger fasteners. I would say the same for the little diesel in the Ram 1500, too. Maybe they are programming them to run low rpm, but how low can they be running? I'm just thinking out loud. Am I way off base?
IMHO, I think you are closer to right than wrong. It seriously takes nothing to nudge a 6.7L into severe service (according to Ford):

• Frequent or extended idling (over 10 minutes per hour of normal driving)
• Low-speed operation/stationary use
• If vehicle is operated in sustained ambient temperatures below -10°F (-23°C) or above 100°F (38°C)
• Frequent low-speed operation, consistent heavy traffic less than 25 mph (40 km/h)
• Operating in severe dust conditions
• Operating the vehicle off road
• Towing a trailer over 1,000 miles (1,600 km)
• Sustained, high-speed driving at Gross Vehicle Weight Rating (maximum loaded weight for vehicle operation)
• Use of fuels with sulfur content other than ultra-low sulfur diesel (ULSD)
• Use of high-sulfur diesel fuel
• Use of biodiesel

 

[dustyroads]

Thanks for the actual list 2015PSD. I think you or someone else had posted the severe service list before, but I couldn't remember all that was on it. It basically looks like Ford is looking for extra oil film in case of either fuel dilution or extra hot, thinned oil.

I know roadrunner has had only stellar results when using 10W30 and i would have no problem using it, myself. If I were to pull heavy weights in mountainous areas, I think I would probably run 15W40 (or 5W40 if starting in cold weather).

 

[claluja]

Related question. I'd love to run 15w40 for summer towing 14k trips, that include excessive idling all night long due to wide load permits. Is there any advantage to the 5w (as opposed to 15w) for excessive idling? Thoughts?

 

[A_Harman]

Originally Posted By: dustyroads
I had the same thoughts as TiredTrucker at first, as my last few trucks have made peak torque way down low (1650 lb-ft at 975 rpm in my Detroit). I cruise at 1100-1200 and spend a lot of time pulling hills from 1200 down to 975 rpm. This is using 10W30 HDEO.

But when you consider the power/torque density of the pickup truck diesels, maybe it's just a consideration of the (rod and main) bearings. The pickups are packing a lot of punch in a small package, even if it is at higher rpm. Due to their size, the crank and bearing size are limited. Whereas a heavy duty diesel is afforded a bigger block, with a longer crank and massive bearings with stronger fasteners.

I would say the same for the little diesel in the Ram 1500, too. Maybe they are programming them to run low rpm, but how low can they be running?

I'm just thinking out loud. Am I way off base?





I think you make some good points. Heavy duty diesels are I-6's, and it is very easy to put large enough rod bearings in an inline engine that have sufficient bearing area to form a safe oil film thickness on 30-weight oil. (Main bearings aren't nearly as subject to this problem, as there are two of them to carry the same load that one rod bearing carries.) Putting the same amount of rod bearing area into a V-type engine is not easy. I don't think it's accidental that the 3.0L Ecodiesel and the 6.7L Powerstroke are both Vee engines and are now requiring 40 weight oil in severe service.

GM has seen the light, and has developed the new L5P Duramax with larger diameter rod bearings that require angle-split connecting rods to make the big ends small enough to fit through the cylinder bores during installation.

I think the OP should run 5w40 in his Powerstroke, even though he is only towing 7000 pounds. He is running through hilly terrain.

 

[roadrunner1]

From what I have read here and other forums many are reading more into the severe service category than what it actually says. With my own usage I have proven to myself that 10w-30 is more than adequate in the 6.7 platform, possibly even superior than a 5w-40 on other points than initial cost. It seems that many are happy spending more for a perceived superior product, when UOA data proves otherwise.

The only way I would ever consider a 40 wt. in the 6.7 is if I were regularly exceeding 240f on oil temp and UOA data were to show increased wear, which I'm not convinced increased wear would be an issue.

There has to be a reason for the Ford recommendation, I'm not sure exactly what that reason is, but I have not experienced a reason to run 40 wt. with just over 53,000 mi. currently. I know there are guys that tow in excess of 80 mph in hilly terrain during hot summer temps, maybe these conditions warrant 40 wt. I don't know. Fluid temps are under such tight control in the 6.7 one has to be flogging it awful hard to reach the point of de-fueling.

This time of the year my commuting consists of short trips with most regens never completed, yet it doesn't seem to affect the oil as UOA's have always come back just fine.

 

[dustyroads]

Thanks A_Harman! I'm just glad that anyone was able to decipher what I was trying to say...I could have written that a little (or a lot) better for sure.

 

[dustyroads]

Originally Posted By: roadrunner1
From what I have read here and other forums many are reading more into the severe service category than what it actually says. With my own usage I have proven to myself that 10w-30 is more than adequate in the 6.7 platform, possibly even superior than a 5w-40 on other points than initial cost. It seems that many are happy spending more for a perceived superior product, when UOA data proves otherwise.

The only way I would ever consider a 40 wt. in the 6.7 is if I were regularly exceeding 240f on oil temp and UOA data were to show increased wear, which I'm not convinced increased wear would be an issue.

There has to be a reason for the Ford recommendation, I'm not sure exactly what that reason is, but I have not experienced a reason to run 40 wt. with just over 53,000 mi. currently. I know there are guys that tow in excess of 80 mph in hilly terrain during hot summer temps, maybe these conditions warrant 40 wt. I don't know. Fluid temps are under such tight control in the 6.7 one has to be flogging it awful hard to reach the point of de-fueling.

This time of the year my commuting consists of short trips with most regens never completed, yet it doesn't seem to affect the oil as UOA's have always come back just fine.


No argument from me, roadrunner. Your UOA's show that 10W30 works great in your application. I'm thinking that if I were running the 11 western states and pulling a considerable load, I would be using 15W40 (or 5W40 in the winter). Too many different types of use to say for sure. I guess I'd have to be in the driver's seat and monitoring the gauges to know what I wanted to use. If I'm not mistaken, I think 2015PSD saw some pretty high oil temps running out west with his PSD.

 

[dustyroads]

Originally Posted By: claluja
Related question. I'd love to run 15w40 for summer towing 14k trips, that include excessive idling all night long due to wide load permits. Is there any advantage to the 5w (as opposed to 15w) for excessive idling? Thoughts?


5W40 is a little less viscous than 15W40 and could save you a little money with long hours of idling. I'm not sure if it would save you enough to pay for the extra cost of the synthetic, but it may cover a good bit of the cost (depending on how much you really do idle). I know many people are able to get synthetic 5W40 really cheap but if not, you have to figure that in. Otherwise I don't see any benefit to running 5W40 (as it pertains to long idle hours).

 

[CarbonSteel]

Originally Posted By: dustyroads
If I'm not mistaken, I think 2015PSD saw some pretty high oil temps running out west with his PSD.
Yep, 240 degrees in Arizona, California, and Nevada with a light load.

 

[mbacfp]

I have seen similar temps as well. In the powerstroke 6.7, what part of the operating engine is the hardest on the oil? Is it the turbo charger when spooling hard?

 

[dustyroads]

Originally Posted By: dustyroads
Originally Posted By: claluja
Related question. I'd love to run 15w40 for summer towing 14k trips, that include excessive idling all night long due to wide load permits. Is there any advantage to the 5w (as opposed to 15w) for excessive idling? Thoughts?


5W40 is a little less viscous than 15W40 and could save you a little money with long hours of idling. I'm not sure if it would save you enough to pay for the extra cost of the synthetic, but it may cover a good bit of the cost (depending on how much you really do idle). I know many people are able to get synthetic 5W40 really cheap but if not, you have to figure that in. Otherwise I don't see any benefit to running 5W40 (as it pertains to long idle hours).


I was probably wrong to say 5W is less viscous, but rather a slightly lower viscosity. At 100C 5W40 is likely to be around 13.5 cSt with HTHS (@150C) around 3.7 or so. A 15W40 is more likely to be more like 15 cSt with HTHS of 4.1 or higher. I'm speaking in general numbers as there are variations in each of these.

The lower viscosity 5W40 would save a little fuel during long idles. When monitoring fuel consumption at idle, it makes a considerable difference in gallons per hour if the oil is warm vs hot. That's where I'm coming from with that. It really does vary depending on viscosity. I've seen 4 gallons/hour with cold oil and at full operating temperature it's more like .8 gallons/hour (in my heavy-duty diesels). If the oil is just warm (maybe 180F), idle fuel consumption is bound to be more like 1.2 gal/hour. Just going by readouts on the dash, it's not exact.

 

[Garak]

Originally Posted By: mbacfp
If memory services me correct...says 10w-30 normal use...5w-40 for severe service (as defined above)...15w-40 If running Bio Diesel.

What's the manual recommendation if you're towing and running biodiesel at the same time, buy a Dodge or GM?

 

[CarbonSteel]

Originally Posted By: mbacfp
I have seen similar temps as well. In the powerstroke 6.7, what part of the operating engine is the hardest on the oil? Is it the turbo charger when spooling hard?
My guess is the heat is generated when hammering the engine (turbo spooling) under a load. I have seen no difference in MPG when using a 10W-30 and so I either run 5W-40 or 15W-40 year round and do not worry about it. The cost savings between using full synthetic for part of the year and conventional the other part versus synthetic blend only is more or less a wash.

Delo LE 5W-40 Full Synthetic (3.25 gallons @ $19.97 each) = $64.90
Delo XLE 10W-30 Synthetic Blend (3.25 gallons @ 14.97 each) = $48.65 ($16.25 less than Delo LE 5W-40)
Delo LE 15W-40 Conventional (3.25 gallons @ 12.57 each) = $40.85 ($24.05 less than Delo LE 5W-40)