Mobil 5w40 turbo diesel syn.

[dmccarty]

I have not run Mobile 5w40 since it is not readily available near me. Shell 5w40 has been and I ran it for years in the Ford 7.3 truck and the tractor. Even going up to close 10K miles on the oil in the truck. An oil change was throwing away perfectly good oil according to the UOA.

I have since switched to JD 0w40 oil since it is a bit better and I get it cheaper than the Shell 5w40.

15w40 in the truck and tractor works in the cold. Not that we get cold compared to our Northern TBNers but the truck and tractor don't like 15w40 oil when the temp is down to single digits or in the 20's. I used to hook the truck to a block heater for easier starts on cold mornings. The 1500 watts for three hours 20-30 days a month adds up.

The truck and tractor starts much better with the 5w40 oil in cold weather. 0w40 is even better.

If the Mobil is diesel rated, easy to find, and decently priced I would give it a try.

Later,
Dan

 

[sw03]

I agree with this 100%. Being the owner of 2 6.0's I use Dyno 15W40. I am not sure I would use anything other than the recommend oil since the injectors are hydraulically operated via engine oil. If it causes a issue it will get expensive really quick.

Chris

This is really nothing new. The older Powerstrokes had foaming issues.

 

[Diamondpilot]

This is really nothing new. The older Powerstrokes had foaming issues.

Not a problem with the engines but with the oil. The real issue was with Rotella and 6.0's but Rotella was reformulated and now its a non issue.

Chris

 

[thatguy]

is Mobil 1 15/50 diesel rated, and are you sure it's recommended to personally custom blend 2 different grades even if it's all Mobil? just asking bb

From what I researched a while back - The ONLY Mobil diesel rated oil (current ratings) is the '5w40 Turbo diesel' - It appears that all the other varieties of Mobil are the VERY old CF diesel oil rating and are intended for current gas engine..

Isnt it the soot in a diesel that required a diesel rated oil? Worst case, what would happen by running a gas oil in a diesel engine?

Brian

 

[GreatWhitehunter]

From what I researched a while back - The ONLY Mobil diesel rated oil (current ratings) is the '5w40 Turbo diesel' - It appears that all the other varieties of Mobil are the VERY old CF diesel oil rating and are intended for current gas engine..

Isnt it the soot in a diesel that required a diesel rated oil? Worst case, what would happen by running a gas oil in a diesel engine?

Brian

The mobil one turbo diesel full syn is approved for use in the 6.0. Rotella was not approved last time I checked. There's a document from ford on the net somewhere that spells it out.

Matt

 

[deerefan]

I found both oils @ my local parts house. After crunching numbers, the mobil would end up costing me about $45 more (for 15 qts.) than the rotella synthetic. I went with the rotella syn (5-40)and will give an update on first oil change. I did notice the truck started easier but can't vouch for fuel mileage yet. Both oils met the required ratings listed in the manual for the 6.0.

 

[dmccarty]

When I switched from 15w40 to Shell 5w40 oil my mpg went up about 3% which is what Shell said at the time. Start up was greatly easier.

A few oil changes back I switched to the JD 0w40 oil and the MPG went up again. Maybe 2-3%. Starts even easier in the cold.

I don't know if it is the oil and/or the truck engine wearing in but I have gotten 21.2-21.4 mpg last summer. Off the top of my head I think the best I did with 5w40 was 20.9 mpg. Certainly 20.5-20.9. My driving route is very consistent and mainly 55mph rural highway driving. Very few stop lights/signs on a 75ish mile round trip. I might hit some stop and go traffic on the interstate from time to time.

I calculate the mpg base on gallons used and mile driven not what the MPG LieOMeter in the truck says.

Later,
Dan

 

[deerefan]

When I switched from 15w40 to Shell 5w40 oil my mpg went up about 3% which is what Shell said at the time. Start up was greatly easier.

A few oil changes back I switched to the JD 0w40 oil and the MPG went up again. Maybe 2-3%. Starts even easier in the cold.

I don't know if it is the oil and/or the truck engine wearing in but I have gotten 21.2-21.4 mpg last summer. Off the top of my head I think the best I did with 5w40 was 20.9 mpg. Certainly 20.5-20.9. My driving route is very consistent and mainly 55mph rural highway driving. Very few stop lights/signs on a 75ish mile round trip. I might hit some stop and go traffic on the interstate from time to time.

I calculate the mpg base on gallons used and mile driven not what the MPG LieOMeter in the truck says.

Later,
Dan

What type of truck do you have? My meter in my F250 is pretty accurate, I check it randomly with a calculator. My mileage has gone up so far about 1 mpg.

 

[patrick_g]

F-250 with 6.4 Powerstroke says 10K miles per oil change unless you use it as a truck and then they recommend 5K miles. I go for the 5k change interval and use dino oil that is fully approved. I don't think I would save $ by using any synthetic I know about. Does anyone get enough increased fuel economy to pay for the difference in the oil cost? I don't think I would.

I'm not anti synthetic just anti waste of $. I have never had a truck engine fail for any reason remotely associated with lubrication. (Actually never had any truck engine fail on a truck I bought new, '97 TD Ram3500 and '08 F250 6.4 PS)

I believe oil is the lifeblood of your engine and try to always change at an appropriate interval and use good filters.

I had a 1964 F-100 (V8) that was propane only and the recommendation on oil change interval on that was to not change the oil. Instruction was to change the filter and top off the oil. It hardly consumed any oil but it got its oil slowly changed due to replacing the oil carried away by the old filters. The instructions also said to test the viscosity of the oil and use lighter oil to top off with, as needed, because the oil tended to get heavier over time as the lighter fractions evaporated. It also recommended 100,000 mile spark plug changes which was just short of a miracle in those days.

Oh, I do use Mobil 1 in my automatic stand by 17KW generator.

Pat

 

[crashz]

I'd like to hear the results of this.

I have a much older diesel engine in my dumptruck and they are known for hard cold starts. The 0w-40 JD oil is very interesting. The 6.2L diesels are very hard on starters, and are plagued with starting issues. When the batteries are fresh, cables clean and tight, glow plugs working perfectly, air tight fuel lines and all constellations in perfect order, she will start. If the 0w-40 lets that starter spin just a bit faster, maybe the starts will be less adrenalin inducing.