So this last week it came time to change the oil in my truck. I ran down to the local parts store to pick up some oil and, a filter. When I saw how much the oil had gone up I about . I usually get the cheap stuff Coastal 15w-40 in gallon jugs. I've been doing some reading about putting diffrent weights of oil in the engine what weights can I get away with that will be cheaper to buy. I've heard 5w-40, SAE30, 10w-30. are just some I've seen on the web and also in the chilton manual.