what is the recommended oil grade to use for a 1996 gmc sierra extended cab 4wd pickup
Usually requires 5w30. some hotter areas may require 10w30 but that's the thickest oil you should ever use in this vehicle - assuming of course this is a gas engine.
I use 5w30 in my 1995 sierra. I'd recommend using the high mileage partial synthetic from castrol if you have over 75k (which I would imagine your 96 would). My truck still runs perfect with 275k with that oil
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