Shell Rotella T6 full synthetic motor oil

[True Grit Farms]

Synthetic oil still burns when I mix it 50 - 50 and burn it in my truck and tractors.

Are mixing used oil in with your diesel and using it as fuel? How does that affect the engine?

Yes I burn a oil - fuel mix year round. When it's real cold it's harder to get the engine to start, and it smokes a little more pulling. I haven't used mix fuels in the newer trucks with the EPA mandatory bs.

 

[Caustic Burno]

Is the synthetic discussion more about ambient temperatures? I am in middle TN and we seldom get below 20°any more. I run 15W40 in all my diesel machines and have had no oil related problems. I do have an old JD that is a PITA to start below 40-50 but I don't think it is oil related.
So it the synthetic advantage more for extreme high or low temperature climates?

I think your problem is the weight. You should probably drop down to ta 10-15.

The first w number stands for winter viscosity.

 

[Banjo]

A guy at the NAPA store said he put synthetic gear oil in one of his disc mowers and he said it was noticeably cooler to the touch than the one that had regular gear oil in it.....after running it for a while.

 

[WinterSpringsFarm]

We run it in our combine, runs wide open 12hrs a day 6 days a week for several months out of the year. It does have some blow by at 3200hrs, but well within spec IMO.

Skid loader and Fendt 822 also run it. No oil consumption in those engines but a lot less hours and not as harsh operating conditions.

I for one am not own the synthetic boat and still run 15-40 in my 2017 Cummins

 

[Bright Raven]

I changed my oil and went to Shell T6 Heavy Duty Diesel Synthetic. I have been mowing all week. It has been in the 90s. Probably the power of suggestion but it seems to have better performance. I cannot qualify or quantify that so just consider it anecdotal.

 

[sim.-ang.king]

In a nutshell the more consistent molecular size resist thermal breakdown for a longer period.
It will breakdown just like conventional in time.

So some newer engines spec synthetic for longer engine life, or longer change invervals, or tighter clearances, or ???

IMOO tighter clearances chasing mileage the other longer change interval and engine life came along for the ride. With synthetic oil you can get clearances down to the molecular level and maintain lubrication. With uniform molecular structure you can get better lubrication along it takes longer for oxidation and thermal breakdown to occur.
Thermal breakdown starts occurring at 240 degrees in conventional oil.
I had to look this one up synthetic can take up to 450 degrees. After all that you get into shear stability testing in an oils abilities to maintain viscosity.
That's my basic understanding from rubbing elbows with research engineers in the refinery. My area of expertise was Cyclic Catalytic Reforming and Hydrocracking.

I would imagine the main thing auto makers are shooting for with using synthetic oil is so they can use lighter oils.
Newest cars are down to 0W-16 so there is very little resistance, which improves MPG's.

 

[Texasmark]

In a nutshell the more consistent molecular size resist thermal breakdown for a longer period.
It will breakdown just like conventional in time.

So some newer engines spec synthetic for longer engine life, or longer change invervals, or tighter clearances, or ???

With uniform molecular structure you can get better lubrication along it takes longer for oxidation and thermal breakdown to occur.
Thermal breakdown starts occurring at 240 degrees in conventional oil.
I had to look this one up synthetic can take up to 450 degrees.

I have proven this to myself by switching from dino to syn oils in my air cooled lawn care equipment. Rather than having to change the oil 2-3 times a season because of dirty oil, I now just change annually, even though measuring around a BS 26 HP Vanguard immediately after a hard workout, other than the exhaust area (around 550F) the hottest spot I could find was 187F with a HF non contact Infrared Thermometer....and it's accurate.

Edit: However, this just hit me. The OHV engine has oil circulating around where the exhaust exits the head (and all) since it lubes the cam and valves. Therefore it is exposed to high temps after all. Maybe not for all that long, but repetitively. So maybe that's the smoking gun that breaks down dino oils.

 

[Caustic Burno]

So some newer engines spec synthetic for longer engine life, or longer change invervals, or tighter clearances, or ???

With uniform molecular structure you can get better lubrication along it takes longer for oxidation and thermal breakdown to occur.
Thermal breakdown starts occurring at 240 degrees in conventional oil.
I had to look this one up synthetic can take up to 450 degrees.

I have proven this to myself by switching from dino to syn oils in my air cooled lawn care equipment. Rather than having to change the oil 2-3 times a season because of dirty oil, I now just change annually, even though measuring around a BS 26 HP Vanguard immediately after a hard workout, other than the exhaust area (around 550F) the hottest spot I could find was 187F with a HF non contact Infrared Thermometer....and it's accurate.

Edit: However, this just hit me. The OHV engine has oil circulating around where the exhaust exits the head (and all) since it lubes the cam and valves. Therefore it is exposed to high temps after all. Maybe not for all that long, but repetitively. So maybe that's the smoking gun that breaks down dino oils.

It's still dinosaur oil just synthetic formula of molecular chains.

 

[ClodHopper37869]

I use either 15-40 or 5-40 Rotella in everything,( 4 diesels, 5 gas ) except my 18 two seat convertible sports car, it gets 0-20 Mobil 1. And I'm giving serious thought to switching it to Rotella when the warranty is up!

 

[Texasmark]

I bought a new '88 Ford 150 with captains chairs and velour upholstery. I can thank it for curing my pack a day problem of some 33 years. Didn't want to stink it up so I just quit.

I do my own oil changes and always fill the new filter prior to installing. I was using dino oil at the time, forget what but a multiviscosity. I'd drain with the oil warm, having just run the engine.

Every time I started the engine, after the fill, i'd get about a second's worth of valve train rattle before the oil pressure filled up the lifters with the dino. I switched to Mobil 1 10w-30 and never had a rattle again. Go figure. Been using 0-20 or 30, depending on the particular vehicle ever sense in them. Funny, my 2009 Hemi was adamant about 5w-20. It was an 864 or 84 and said the cylinder shutdown wouldn't work with thick viscosity oil.......well pilgrims (John Wayne) what about the bearings and all....it is a Hemi, built for tugging.