I just purchased my truck a few months ago, and I run a lawn company. My question is.....Will I benefit anything from synthetic oil over regular oil if I change it every 5000 miles. The reason I ask is because my truck gets started and shut off 25-30 times a day. Will that cause the oil to break down? Not trying to start a war, just wanting to know if you thought regular oil would stand up to being stopped and started numerous times daily.

 

regular oils has a flash point of 400 degrees F synthetic 's flash point is above 600 degree's ..........

so IMO you'd be less apt to have a 'coking' problem in the turbo bearings with synthetic oil if you don't cool down enough when shutting down

 

Actually, you could go synthetic and change your oil once every 7500 miles. That's what's recommended when your putting your engine through some tough miles. If you aren't putting a lot of hard miles on it you can change your oil every 10,000 miles if you want.

 

If you change you oil every 5K miles , you could use anything. Well, any oil. To answer your question, no. There will be no advantage. Now if you were to go with extended oil drains, yes. Synthetic oils do not break down. They get dirty. Dino oils DO break down and need changing. If you can clean the synthetic and just add back for the filter and top it off, whatever you use as far as the additives are concerned, will be return with that added oil. I run the dual by-pass and change my oil completly, once a year. I change the full flow filter 3 times at 7500 miles then the by-pass filter the third time. So far 296K miles and numbers are good.

Did that answer your question? I hope so.

..Preston..

 

Every time synthetic oil comes up I remember the contents of this link: http://irv2.infopop.cc/6/ubb.x?a=tpc...2&m=3596097864 I'll never waste my money buying super refined dyno oil that's called synthetic just because a court said they could.

 

That is some interesting reading Ray...I've always wondered what the deal was w/ that. It's no wonder the oil companies are so rich!

 

For a 5,000 mile oil change interval on the Cummins, a conventional petroleum diesel oil will work just fine.

I just checked the oil report from my Cummins when I was running amsoil 15W-40 full synthetic, and the flashpoint value on mine was 415F, well below 600F. So I guess I wasn't getting what I was paying for.

True, group 3 hydrocracked petroleum oil can be sold as synthetic is the US. If one is not into extending their oil change interval, and want the cold flow characteristics for wintertime, this stuff may fit the bill for them. While being expensive, they're usually not as pricey as the full synthetics. Even amsoil markets a line of this oil, and calls it synthetic!