I always change my oil twice a year, no matter how little I drive, or every 10.000 km anyway. This despite the car manual only says oil needs be changed every 40.000. Also, whenever I start a trip longer than 200km, I check the oil and add a little if it's dropped any.
Dee
"When life's a biatch, be a horny dog"
Amps: Marshall JVM 410H w/ Plexi Cap mod, Choke Mod & Negative Feedback Removal mod, 4x12", Behringer GMX110, Amplitube 3/StealthPedal
Half a dozen custom built/bastardized guitars all with EMG's, mostly 85's, Ibanez Artwood acoustic & Yamaha SGR bass, Epiphone Prophecy SG, Vox Wah, Pitchblack tuner plus assorted pedals, rack gear etc. for home studio use.