The major consideration was $$$$imple- - - - - -buying it in pails instead of quart bottles was cheap! Any oil with the gear-shaped API symbol for a particular application means it passes some very strict standards, and I've never heard of Diesel-rated oils giving problems in gasoline engines, at least during the 50-something years I've been using them that way. Dad used to use RPM DELO (Diesel Engine Lubricating Oil) in flathead Ford racing engines back in the 1950's, and I did the same thing on dirt track Chevy 327's in the late 70's- - - -never had an oil-related bearing problem that I can remember!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!