I don't drive many miles per year or tow. In the past year and a few months I've totaled ~9000 and that was with a 2500 mile trip. The rest is city driving with mostly a 13 mile round trip to work. I'm in a very hot climate location. The truck is fairly new to me and I am currently using M1 0w40. The previous change used M1 5w30 HM and was pretty dark. I don't know which oil was used by the previous owner. I've heard this engine is easy on oil. 1. I change the oil/filter at 5k intervals. Considering such low annual miles, I was thinking of switching the filter every other time. The filter isn't that big and the sump takes about 6.5 quarts so I wouldn't think that the small amount left in the filter will affect the integrity of the new oil. It would mean putting the truck up on ramps and removing the skid plate only once a year, too. 2. The manual calls for 5w30, but considering the rave reviews and specs of M1 0w40 I thought I'd try it. The truck was a tad bit more sluggish before warming up, I thought, but I haven't noticed a drop in MPG. If I wasn't using this oil, I'd probably be using M1 5w30 HM, which I used for years in my last truck. So, should I double the filter interval and should I still use the M1 0w40 or go back to the M1 5w30 HM? If not that 5w30 (maybe a 0w30???), which has the same accolades as 0w40? Thank you.