Engine Oils

my dash few min ago, 1,457,000 miles, Volvo 780/ volvo D13 original ; I use synthetic only Shell Rotella T6 5w40; about 30,000 miles change inteval; did the oil help? I dont know, but i read a lot about synthetic oils and i have no doubt the synthetic are superior in any kind of motor;



From Wikipedia synthetic oil:
Advantages
The technical advantages of synthetic motor oils include:

Better low- and high-temperature viscosity performance at service temperature extremes[citation needed]
Better (higher) Viscosity Index (VI)[citation needed]
Better chemical and shear stability [5]
Decreased evaporative loss[citation needed]
Resistance to oxidation, thermal breakdown, and oil sludge problems[citation needed]
Possibility to extended drain intervals, with the environmental benefit of less used oil waste generated[citation needed]
Improved fuel economy in certain engine configurations[citation needed]
Better lubrication during extreme cold weather starts[citation needed]
Possibly a longer engine life[citation needed]
Superior protection against "ash" and other deposit formation in engine hot spots (in particular in turbochargers and superchargers) for less oil burnoff and reduced chances of damaging oil passageway clogging.[citation needed]
Increased horsepower and torque due to less initial drag on engine[citation needed]
Improved Fuel Economy (FE) - from 1.8% to up to 5% has been documented in fleet tests[unreliable source?]
DisadvantagesEdit
The disadvantages of synthetic motor oils include:

Substantially more expensive (per volume) than mineral oils.
Potential decomposition problems in certain chemical environments

 

I don't think you can go wrong with any of the major brand oils recommended for your engine. An important part is running a good quality filter. I know guys who go out and buy the most expensive synthetic oil they can find for there car and then throw a cheapo garbage Fram extra guard filter on it.

 

Mobil Delvac is a synthetic oil. My engine runs smoother, idles quieter. I don't know of any impact on mpg.

 

I just use a synthetic blend I get from Schaeffer Oil. I buy by the drum and get pricing that meets or beats anything that one can get at Wally World and it is shipped free to my front door with free oil sample kits and analysis thrown in.

But any of the major oils are fine. But oils and engines are similar to .22 caliber rifles and ammunition. While all the major brands of ammo are well made, some rifles just prefer and shoot better with particular brands of ammo. One of those little mysteries of life. Engines tend to do the same thing. For some reason, some engines do best on Mobil. Some do better on Rotella. While still others seem to do best on Delo or another brand. Each one of those oils has proprietary mixes in their additive packages that are different. The base oil, be it conventional or synthetic, is the same. It is the 20-25% of what you get in that gallon of oil in additive package that makes the difference.

Filters are important also. I have a preference for Donaldson Extended Life filters myself.

Viscosity can make a difference as well. All the OEM's are factory filling with 10w30 HDEO now. No one at the factory is filling with 15w40 anymore. A viscosity can make a little bit of difference in mpg, but I am not sure an individual can fully prove it. Only in fleet operations with hundreds of trucks can anyone truly put together stats that prove something like that. There are so many variables that affect fuel mileage.

I took a Cummins N-14 to 1.4 million miles on a conventional Kendall 15w40 doing 30,000 mile oil changes. No bypass. All it ever got in that time was one accessory drive seal and one injector. Brand of oil or whether it is conventional or synthetic might have some impact, but how one treats the motor and maintains it will do more for longevity than anything.

 

yes brands do matter, the cummins isx NEEDS rotella T(non synthetic), most of the mega fleets will do some ####ty extended pm's with delco to save money and ruin the engine, but they dont care if it needs a rebuild at 600k because they will sell it off at 450k

 

School us, why does a ISX need Rotella T?

 

All comfy here on my stool at the lunch counter.....tell tell!! Why have my Cummins (3 N-14s & 3 ISXs) done just fine on Schaeffer; yet "NEED" Rotella??

 

I have had a preference for Schaeffer oil for some time myself. I really like their grease also.

When I mentioned that brand is important, I did not mean that one particular brand is the perfect selection for an entire line of motors. It is a lot more specific than that. Each individual motor shows a definitive preference for a particular brand of oil. One has to do regular sampling, and if the oil is not performing as it should, then change to another brand and repeat the process. Find the one that does a great job and stick with it. I would take issue that Rotella is the best selection for the entire ISX line. A good oil, for sure, but not every ISX is going to agree with it.

 

I see very little conversation about the brand of filter used. This makes a huge difference per the chart from Bob the oil guy.
My dog loved the JT8, started better, idled smoother and slobbered much less plus an increase of lube psi across the board. Because of my lease and the style of operation I ran a severe duty schedule of 10k.

MPG's were just that, no change but that was my environment of heavy load short haul with long pump idle.

I also threw TCW-3 in with every fuel to compensate for lost lubricity in ULSD. A little more expensive to fuel yes but IMO kept me out of the dog house. ( pun intended ) ( 16oz per 26 gals ) Caution! Do not use any additive on DPF units or catalytic units, it will plug the converter. My dog was old school, turbo to stack .

JMO