Just spotted 15W-30 (no, not a typo, 30) diesel oil from Chevron Delo...
http://www.chevronlubricants.com/en_US/products/products/Delo_400_SD_SAE_15W-30.html
If your in Florida or Texas, or another hot area, this may be worth considering...
Matt,
be careful about the "oils" .......
make sure we understand what the terms mean, and no - I am not trying to be ugly
- but way too many people in the real world do not understand those two numbers (and tractor/car/truck people too).
FOR example - there are those THAT STILL put 30 weight oil in there 50 year old tractor - BECAUSE that's what WAS available then and that is what was called for.....
Here in Virginia - we can get in the single digits and the triple digits, we need a multi viscosity oil that can start up easily and then protect as the machine is sweltering in the 95% humidity and 95d temps.
In very basic terms the first is the viscosity of the oil at a certain temperature, and the lower the # the easier it is to pump/flow. So a 5 will pour better in the cold than a 15 and so on WHEN cold. Now - there is a problem there, as the temps start to rise....the oil will flow too fast and then will not provide the "cushion" between the surfaces and the pressure will drop too!
SO - in the old days, you HAD to change the oils - low number in winter and then higher in summer, as the summer blend heated up, because it was a thicker base, it would not thin out as fast as a winter blend would in the summer.
SO - man being the smart sumbeauches they are - found a way to make a oil "thicken" as it gets hotter.......now there is a real trick! Make an oil behave like a thicker oil AS IS gets hotter!!!!! SO - the multi viscosity was invented. AND in the olden days - you could have 20-50, 10-30 and so on....
NOW - those little chemists in the back row are making oils that pour like water and can protect like 80 weight oil!!!! OK - aint quite there yet, but you get the idea!
The "newest" oils on the market are those that flow reallllll easy! and have a lot less friction involved when being pumped and placed in between tight fitting areas. The typical oil for new cars is 0w20......flows like 0 weight, protects like 20 weight when hot. They do that for many reasons, gas mileage is the main reason.
here is a great site that explains "oils" and viscosity in layman's terms.
http://www.upmpg.com/tech_articles/motoroil_viscosity/
oils in the future will spread the spectrum further, hell there might even have little machines that are IN the oil that somehow fix places that have been damaged - and only when the little nanites are broken down will you change the oil!
then again ....man wont be driving then ......damn cars will be driving and FIXING themselves!
