I use a Thailand made 2003 Ford Ranger, crew cab, 4x4, packing a "big block" 4 cyl 2.6L with 23,760km on the ticker. It still has the original oil and filter. They oil looks like crude oil. It has developed an established tapping noise eminating from the valvecover. I was able to locate three 20mmx1.5 oil filters used on john deere gators from another base and plan on putting one on the ranger and dumping some Amsoil AME in there to help out with the tapping and/or future wear. This vehicle is a workhorse from getting water to hauling trash to hauling part for military vehicles on this FOB. It has no history of maintenance and is quickly starting to show. BTW it is over 110F ambient everyday during summer with dust storms every three days. The military does not stock parts for this vehicle so it's at the mercy of the operators to maintain it. I can order 5w30 conventional oil from another base but it will take a month or two to get out here. Let me know if the AME will do more harm than good or should I hold out until I can get the 5w30 re-recyled oil(Safety-Kleen). I can also stab in some 15w40 re-recycled that I have on hand right now for our other vehicles. Thanks.