Oil Changes always have been and for the foreseeable future will continue to be the cheapest and easiest insurance for your engine.
Failure to change the oil in your car can lead to several problems, which I'm sure everyone knows by now, the worst case scenario being an engine seizure. Low oil pressure can also lead to poor performance.
The reasoning behind an oil change is simple, as the pistons slide up and down in the cylinders, they shave tiny pieces of metal off of the walls of the cylinders, this, in addition to any debris picked up during anytime the block was opened, or from any of the reciprocating parts in the engine. Oil as a lubricant is fine, but once too much debris is introduced for the oil filter to handle that debris will backup in the filter clogging it to the point that the oil in the crankcase gets used up and without anything to refresh the lubrication the engine eventually becomes a large paperweight.
Modern engines are more efficient, therefore do not need oil changes as often as an older engine, however they still need to be changed fairly regularly.
Mitsubishi's oil change interval of 3,000 miles is the indicated "severe" driving, which includes city driving, short drive times, long distances at low speeds, long idle times, dusty driving, driving in temperatures above 90 or below 0 F and several other factors, if your car routinely handles any one of these factors you are driving the car in severe conditions and need to change the oil at 3,000 miles.
Almost as important as the oil change is the set interval to check the other fluid levels in the car, Brakes, Transmission, Power Steering, Windshield Washer, Battery, and Clutch. Most places will top these fluids off during an oil change free of charge. If you're really organized you can remember to change your air filter every ten oil changes (30,000 miles.) This is also a good time to run through a quick safety inspection.
As far as price goes you can have your pick, doing your own oil changes usually will not void your warranty and there is not a Jiffy Lube in the country that does not warranty their work. Doing it yourself is an easy chore for a Saturday afternoon and gives you a sense of pride when you're finished.
Oh wow I ramble when I've been drinking.
<center><img src="http://czm.racknine.net/images/bobimpactfog.gif"><br>
Thanks, FlufferNutter and CZM! - <a href="http://bobimpact.coolfreepage.com/">Ron and Fez Drop Archive</a>
My Head is Bloody but unbowed.
Ron and Fez live in NYC or the real nightmare begins.</center>