I have a 2005 Dodge Ram 1500 Quad Cab V8 with 150,000+ miles on it.
I usually do it the first weekend every month regardless of mileage. Every time I go in the guys at the oil change place are always amazed how clean the expelled oil is.
I recently had the u-joints replaced, one was making noise. Just three weeks ago I got front rotors and new brake shoes all around for the first time. The mechanic was totally amazed.