Beware claims that the military uses it. They might- but they buy any oil from anyone that can meet basic specs. Lowest bidder, etc.

...speaking as an engineer on 2 ships, the Navy uses the cheapest 2190 (40weight) mineral oil available for reduction gears that can handle in excess of 50,000HP per set- and LOTS of filters and purifiers. Change interval = overahul interval, about 10 years (150,000 miles, assuming 5 deployments @ 25Kmiles per). We sample 2x/day when in use for visual inspection of particulate and water and maintain constant temp. 10 year old 2190 looks a more amber than fresh, but is still very much in spec...and the Navy knows a thing or two about keeping gears running.

Diesels use 9250, which is 40wt with detergent. Change interval varies, but as I recall it was several hundred hours in general. Diesel engine oil is the only type that gets regularly changed, because of combustion products and inevitable fuel dilution.

Gas turbines and hi-speed generators use synthetic- change interval = lifetime. Again, LOTS of purifiers and filters. BUT these oils never come in contact with combustion products- purely rotational lubrication.

So a synthetic manufacturer may well claim 'never needs changing' and' used by the military' and be telling the truth- sort of. But they are probably obscuring which oil is used for what purpose.

These guys should stick to commenting about their oils, and avoid speaking anecdotally and out of context about CVTs, engine life, ANYTHING that is not directly in their line of business- lubricant engineering. Pretty good advice in general, for anyone, come to thnk of it.