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Baradium · 05-28-2003, 07:39 PM

You guys ever check the owner's manual chart for oil?

For hot climates, like the desert in the summer, it calls for 20W-50, and this was for the brand new engines when these trucks were new. In fact, it says you can use straight 30W motor oil in some temps (small range). The one that gives you the best temp range is 10W-40 (covers all 10W-30 ranges because of the 10W when cold and also covers more upper temp ranges than 10W-30). With synthetics a 0W-40 or 5W-50 or so would seem to be a good combo. A thinner oil might slightly help your economy, but these engines weren't designed for it and it can hurt engine life.

I'm wanting to try amsoil in the scout once I get my dual drain plug pan in, and then in the '70 later. (amsoil gives you a longer drain interval, you just check the oil and I've heard of upwards of 100,000 miles with just changing the filter and putting that extra quart back in). I've seen reports that amsoil can reduce oil consumption too, don't see how but I'm curious about that.

05-28-2003, 07:39 PM	#22
Baradium Binder Rep Join Date: Jan 2001 Location: Salcha, AK Posts: 1,506	Oil? You guys ever check the owner's manual chart for oil? For hot climates, like the desert in the summer, it calls for 20W-50, and this was for the brand new engines when these trucks were new. In fact, it says you can use straight 30W motor oil in some temps (small range). The one that gives you the best temp range is 10W-40 (covers all 10W-30 ranges because of the 10W when cold and also covers more upper temp ranges than 10W-30). With synthetics a 0W-40 or 5W-50 or so would seem to be a good combo. A thinner oil might slightly help your economy, but these engines weren't designed for it and it can hurt engine life. I'm wanting to try amsoil in the scout once I get my dual drain plug pan in, and then in the '70 later. (amsoil gives you a longer drain interval, you just check the oil and I've heard of upwards of 100,000 miles with just changing the filter and putting that extra quart back in). I've seen reports that amsoil can reduce oil consumption too, don't see how but I'm curious about that.