[mickey356]

Maintenance book says to change oil and replace filter every 15K.
Also under Severe Condition Maintenance
More frequent maintenance than specified in the Maintenance Schedule is required if you drive under severe operating conditions. They include:
More frequent engine oil and filter changes for extended idling or low speed operation.
More frequent engine oil, oil filter and air filter replacementsunder severe dust condition, driving on unpaved roads or off road.
Frequent cleaning of radiator grille and core to prevent debris from restricting the cooling system (928, 944)
Cleaning and bleeding of fuel system may become necessary if contaminated by water, foreign matter, dirt or residue.
Owners Manuel says Oil Temperature has an influence on the service life of the engine. After starting the engine, drive at moderate speeds until the oil temperature gauge needle has reached the end of the white field. When the needle has blimbed to the first white line of the scale, the engine has reached operating temperature (194 F/90 C). etc.....

I've had my car for 4 months (4k miles) and have changed the oil and fitler twice. Being that it's recommended to change every 15K is it save to say I'll be OK changing every 3-5K?
It's not that I only drive it 10 miles a day but more often than I'd like I am running around town. I get it out on the highway or through the back roads about once a week. I'd really hate to not be able to enjoy my car. As much as I really (REALLY) like driving on the highway and back roads I still like driving my car all the time regardless.

As an afterthought - I still can't wrap my head around the "getting the car to operating temp" thing. How can it be an issue if you don't always get your car to 194F when driving? Regardless of how long you drive the car if the car starts cold (needle at the bottom of oil temp gauge) you still have to get it up to operating temp. So doesn't the engine have to run "cold" until it gets to temp? How is it starting a cold engine and getting to temp is anymore beneficial? Whether you reach operating temp or not the engine still has to run cold for awhile, no? Why is always getting it from cold to 194F important? What if you drive in a place where the temps are bitter cold in the winter and regardless of how long you drive the car can't get to 194F? Are you not supposed to drive? I'm confused as to why Porsche (Germany, where it gets cold) would make a car that can only be driven in fair weather climates. I know I may sound dumb asking these questions but it doesn't seem right to me. I'm sure I'm missing something here. The wear and tear physics of it don't seem to make sense if you're always starting cold.