I had an 86 Ford 150 straight 6. Changed every 4,500 , but the last 30k I didn't change. Never burned much oil. My 96 F150 6 got changed even less. My 05 GMC diesel sued to get changed every 40,000 mi. with Amsoil series 3000 HD diesel with filter every 15k. Decided Amsoil was too much hassle to get. so I went with Shell Rotella 10w30 ( Yellow) and change every 10K and the change oil light comes on almost exactly every 10K anyway. I now have 11K on the Shell 5w40 syn. and will change it in the spring for about 14K? Those oil analysis are really the way to go if you really want to know, otherwise we are all guessing but 5 qts in a car really is cheap. Trucks with 10-18 qts can really get expensive Twenty oil changes every 100k will set you back $1,000 . If you really can get away with every 10K, that is a fairly decent rifle right there. For now on I a going full syn. now that wife got a nice 09 Pontiac G6 2 dr. and I bought an 04 Malibu . All 3 outs used very little oil so I will go with Shell Rotella , Mobil 1 Or find Amsoil . I ran AMsoil for 35k in my cars several times . The engines never failed. We change oil too much. Seems air filters are just as important for clean oil .


But the fruits of the spirit is love, joy, peace, patience, kindness, goodness,faithfulness, Gentleness and self control. Against such things there is no law. Galations 5: 22&23