mine is a daily driver to and from work at least 70 miles a day. the cost of serv. is a bitch. after reading the oil basics1&2 have decided to start useing mobil1 20w50 motor mbl 1 75w90 trans then go 5000 mile . have noticed that during the hot summer that the conv. oil realy turns black esp. if you go over 2500 miles . for the same price as hd conv. oil i can run mobil 1 20 w 50 and fig. it wont hurt to go 5000 miles.jmo