I've been debating using the Motorcraft 10-30 CJ-4/SM diesel oil. My 07 6.0 has 12,500 miles on it. I do not tow or haul, other than maybe a rocking chair, couch, soccer mom stuff. other than that it's 60% City, 40% hwy. I drive "normal", not hot rodding, and I do not have a chip. 35" AT and a 4" exhaust only. What do you guys think?
10-30 HDEO IN 6.0?
- Thread starter Toy4x4runner
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It's hot enough there year round that I'd be tempted to just stick with 15w40, those motors are hard on oil.
Why the 10w30? In Fla. I would run straight 30 it would work great. Should protect better than the 10w30 due to the better HTHS.
Originally Posted By: Toy4x4runner
I've been debating using the Motorcraft 10-30 CJ-4/SM diesel oil. My 07 6.0 has 12,500 miles on it. I do not tow or haul, other than maybe a rocking chair, couch, soccer mom stuff. other than that it's 60% City, 40% hwy. I drive "normal", not hot rodding, and I do not have a chip. 35" AT and a 4" exhaust only. What do you guys think?
Nope. The HPOP oil pump on a 6.0 shears the hades out of oil. That 30W will be down in the 20W range.
If you want a 30W oil, put a 40W in it and it will be sheared down to a 30W.
I've been debating using the Motorcraft 10-30 CJ-4/SM diesel oil. My 07 6.0 has 12,500 miles on it. I do not tow or haul, other than maybe a rocking chair, couch, soccer mom stuff. other than that it's 60% City, 40% hwy. I drive "normal", not hot rodding, and I do not have a chip. 35" AT and a 4" exhaust only. What do you guys think?
Nope. The HPOP oil pump on a 6.0 shears the hades out of oil. That 30W will be down in the 20W range.
If you want a 30W oil, put a 40W in it and it will be sheared down to a 30W.
dnewton3
Staff member
I guess it would depend on how often the OP was going to OCI. Toy4x4Runner, are you going to get UOA's, or just OCI every X,xxx miles?
My neighbor runs 10w30 in his 6.0 PSD in the winter, here in Indiana. With the 10w30, he get's better start up and cold idle quality (no "romp", which can sometimes be an issue with a HEUI system). Then he changes to 15w40 in the summer. I just talked him into getting a Fumoto valve, for the purpose of UOA's.
Overall, being in Florida, I see no reason for the OP to run a 10w30. A 15w40 would be fine, and is the preferred viscosity. Further, I'd take a multi-weight any day over a straight weight, ESPECIALLY in a HEUI system. Thick, straight-weight oil does not help promote start-up, and casues drivability issues until fully warmed. Multi-weight is recommended for a very good reason.
Just a technical insight here; it's not the HPOP that shears the oil, it's the action of the oil inside injectors themselves. The 6.0 uses HPO to both open and close the injector. The old 7.3 PSD used the oil to open the injector, but a spring closed it. However, in both systems, the shearing takes place in the injector chambers; it's just twice as often in the 6.0 PSD. That being said, it's true that the HEUI does certainly shear the oil down, but it doesn't drop overnight. It's somewhat progressive over time. It's definitely a concern, but I see it as just one more thing to monitor in a UOA, like the wear metals, insolubles, TBN, ect.
My neighbor runs 10w30 in his 6.0 PSD in the winter, here in Indiana. With the 10w30, he get's better start up and cold idle quality (no "romp", which can sometimes be an issue with a HEUI system). Then he changes to 15w40 in the summer. I just talked him into getting a Fumoto valve, for the purpose of UOA's.
Overall, being in Florida, I see no reason for the OP to run a 10w30. A 15w40 would be fine, and is the preferred viscosity. Further, I'd take a multi-weight any day over a straight weight, ESPECIALLY in a HEUI system. Thick, straight-weight oil does not help promote start-up, and casues drivability issues until fully warmed. Multi-weight is recommended for a very good reason.
Just a technical insight here; it's not the HPOP that shears the oil, it's the action of the oil inside injectors themselves. The 6.0 uses HPO to both open and close the injector. The old 7.3 PSD used the oil to open the injector, but a spring closed it. However, in both systems, the shearing takes place in the injector chambers; it's just twice as often in the 6.0 PSD. That being said, it's true that the HEUI does certainly shear the oil down, but it doesn't drop overnight. It's somewhat progressive over time. It's definitely a concern, but I see it as just one more thing to monitor in a UOA, like the wear metals, insolubles, TBN, ect.
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I guess I'll stick with 15-40 CJ-4/SM motorcraft Or 5-40 Rotella.
I'd go with a 5w40 as it's more shear stable than some other options and will still give you the cold flow properties you are looking for. I would strongly recommend not using 10w30 in a HEUI engine, even a lightly loaded one.
10-4 guys. 5-40 it is.
Originally Posted By: Arkapigdiesel
Originally Posted By: Toy4x4runner
I've been debating using the Motorcraft 10-30 CJ-4/SM diesel oil. My 07 6.0 has 12,500 miles on it. I do not tow or haul, other than maybe a rocking chair, couch, soccer mom stuff. other than that it's 60% City, 40% hwy. I drive "normal", not hot rodding, and I do not have a chip. 35" AT and a 4" exhaust only. What do you guys think?
Nope. The HPOP oil pump on a 6.0 shears the hades out of oil. That 30W will be down in the 20W range.
If you want a 30W oil, put a 40W in it and it will be sheared down to a 30W.
Thats the point of using a SAE30 monograde, to virtually eliminate mechanical shear.
Originally Posted By: Toy4x4runner
I've been debating using the Motorcraft 10-30 CJ-4/SM diesel oil. My 07 6.0 has 12,500 miles on it. I do not tow or haul, other than maybe a rocking chair, couch, soccer mom stuff. other than that it's 60% City, 40% hwy. I drive "normal", not hot rodding, and I do not have a chip. 35" AT and a 4" exhaust only. What do you guys think?
Nope. The HPOP oil pump on a 6.0 shears the hades out of oil. That 30W will be down in the 20W range.
If you want a 30W oil, put a 40W in it and it will be sheared down to a 30W.
Thats the point of using a SAE30 monograde, to virtually eliminate mechanical shear.
dnewton3
Staff member
Perhaps I am under a mistaken assumption, but I don't agree, Max Wander.
Any oil is capable, given the right circumstances, of shearing down in viscosity; so a monograde would shear down. Perhaps not as fast, but it would shear.
Further, I believe that the benefits of multi-weight oils at start up FAR outweigh the claims of a monograde for the OP's application.
In my mind, monogrades are excellent for engines that rarely get shut down, running very heavy loading cycles. I'm thinking of large generator sets, HEAVY excavation equipement run 24/7 like in a mining operation, OTR tractor trailers that run non-stop, and the like. Here, they come up to temp and stay there for weeks, until the next OCI. Any oil has a saturation point with additives. The monograde has no VII's, so it can carry more of other additives such as detergents, dispersants and such. That's why a monograde is good for long, sustained heavy operation. Multi-grades are suited best for intermittent operation, like most personal use vehicles.
Monograde doesn't belong in a light duty diesel truck; especially one that is going to be driven like a "soccer mom". In the OP's environment (FL), a 15w40 is the perfect and clear choice. The brand choice is up to him; all do well.
Any oil is capable, given the right circumstances, of shearing down in viscosity; so a monograde would shear down. Perhaps not as fast, but it would shear.
Further, I believe that the benefits of multi-weight oils at start up FAR outweigh the claims of a monograde for the OP's application.
In my mind, monogrades are excellent for engines that rarely get shut down, running very heavy loading cycles. I'm thinking of large generator sets, HEAVY excavation equipement run 24/7 like in a mining operation, OTR tractor trailers that run non-stop, and the like. Here, they come up to temp and stay there for weeks, until the next OCI. Any oil has a saturation point with additives. The monograde has no VII's, so it can carry more of other additives such as detergents, dispersants and such. That's why a monograde is good for long, sustained heavy operation. Multi-grades are suited best for intermittent operation, like most personal use vehicles.
Monograde doesn't belong in a light duty diesel truck; especially one that is going to be driven like a "soccer mom". In the OP's environment (FL), a 15w40 is the perfect and clear choice. The brand choice is up to him; all do well.
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