Engine oil

[Jaeger]

I used Rotella dino 15w40 for ever with no issues. Unable to find any of it on shelves and recently moved to the Castrol GTX Diesel 15w40. Reasonable price, CK4 rated, and seems more than adequate for my 50 hour oil and filter changes.

No issues with cold being in Pa winters either.

 

[droy]

Saying that Product X is made in the same place (town, state?) or by the same company as Product A or Product B is a common bit of disingenuousness often employed when someone selling Product X wants to imply it as good as A or B. The same company may produce A, B, and X in the same plant but to different specifications according to what the brand wants to pay. In the case of oil, that may include the basic feed stock as well as different additives. As big bubba pointed out, go with the API service and viscosity ratings in your owner's manual or what your dealer recommends, at least for the warranty period.
I am also in favor of an oil analysis at each oil change, or as recommended by the laboratory if you are extending the change interval.

Adding a little to what Big Bubba & Captain Dirty previously stated; Make sure the oil meets the engine manufacturer’s specs. The “API” (American Petroleum Institute) specs are posted on every container of motor oil for that reason. As an owner / operator hauling base & lube oils to different blending plants throughout our nation, I have had the opportunity to speak to & learn from very knowledgeable people in this part of the oil business.
There are not that many refineries in the USA that produce base / lube oils & even fewer do their own blending. We haul base or lube oils from refineries to blending plants where certain additives are added then jugged & labeled. Simply put, at these blending plants each “oil manufacturer” has their own tank of “secret sauce” aka additive that is injected into the base oil then dumped into the container “de jour” which can be anything from quarts going to an auto parts store or into a rail car or tank truck going to a auto manufacturer.
If you walk through the blending area of a plant filling gallon jugs you could very well see a very looonnng conveyor line with jugs of a certain color then 5-10 neutral jugs then more jugs of another color, indicating a switch from one brand to another. The neutral jugs were there to clear the additive injection lines insuring quality. Long time ago the “slop” in the neutral jugs was given to employees for personal use. Many used this slop for oil changes in new vehicles newly purchased. At one particular plant during a break, I had asked if there were ever any problems encountered from them using this off spec oil, no one had a bad story.
Another interesting thing I found out years ago is that at that time, only one oil manufacturer produced a TRUE synthetic oil, & even they were considering also going dino based. Oil companies had successfully lobbied our government to allow dino based oils to be labeled full synthetic which I’m sure was way cheaper then manufacturing a synthetic base.
Sorry for the long post, just wanted to share.