Twice a year, just before summer and just before winter using Penz. Plat. synthetic oil. It takes me more then a year to hit 5k miles so I just do it twice a year when the weather is nice and cool (spring/fall). That's the way I have done it with my mustang and that's the way I'm going to do it with the ranger.

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95 Mustang GT 5.0 former daily drive of 11 yrs. now weekend toy.
99 Ranger XLT 3.0 new daily driver. Totaled 3/13/2015
00 Ranger Base model 4x4 3/28/2015