I prefer something a little heavier than 10 weight, which is the physical thickness of 10-30 all the time. It just lubricates like 30 when it's hot. I've been using 15W-40 in all my vehicles for several years, including a couple that needed 5W-30 when new. After 100,000+ miles, I think the clearances are probably wide enough to need a thicker base oil. Since I use 15-40 in the farm tractor, it makes sense to me to buy it in bulk and use it in everything.
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
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