Here's why you no longer need to change the engine oil at 3k mile intervals on modern engines:

Back when your Dad, Grandfather, and your uncles all learned to drive, car engines were much dirtier machines. They used leaded gasoline, had points ignition systems, and used carbs that basically dumped as much gasoline as they could because there weren't any emissions regulations that restricted that.

Also, these engines had tolerances that were so loose, you could put a piece of paper between the piston ring ends with the rings installed in the cylinder bores, and that was acceptable for a clearance.

So, as the cars ran, gasoline would get past the piston rings, and contaminate the low quality engine oil, and shorten its already short lifespan quite tremendously.

Over the years, improvements have been made in all those factors.
- Engines from all manufacturers are built to tolerances that were simply unheard of 40 years ago.
- Emissions regulations have removed leaded gasoline, and require that engines have strong ignition sparks to fully ignite the fuel mixture, and burn it completely.
- Multi port fuel injection systems have eliminated carbs from all cars, allowing each cylinder to use exactly the amount of fuel it needs, and engines all run on the lean side from the factory.
- Engines run so much hotter today that 20 to 40 years ago, that the engines, pistons, cylinder heads, piston rings, valves, and all other components are now made of lighter materials that conduct and expel heat much more efficiently, that higher quality engine oil is required in order to keep these engines from seizing up just on your normal ride into work every day.

Since the engines are tighter, and run leaner, less unburned gasoline gets past the piston rings and into the oil to reduce its ability to lubricate the engine, and carry heat away from critical moving parts inside the engine.

Since the engine oil is less contaminated, it doesn't need to be changed as often.

Also, in the Chrysler Crossfire, you are using a fully synthetic engine oil, that is required to meet one of the most demanding engine oil standards - The Mercedes Benz 229.31 and 229.51 standards. Very few engine oils meet these standards, and only synthetic oils actually do meet this grade. (If you aren't using synthetic oil, you are doing your engine a disservice)

Then, there is the small fact that your engine contains 8.5 quarts of the best oil on the market. The larger the pool of oil, the lower the level of contamination, and the longer that large pool of oil can go between changes.

4 quarts of oil gets worn out quicker than 8.5 quarts of oil under the same operating conditions due to the simple fact that the oil gets circulated more times than the larger amount, and has to work harder at protecting the engine parts during that period of time.

Anyway, its entirely up to you how often to change your engine oil.
What I will always recommend to someone who is unsure, like I believe you might be, would be to have an oil analysis done at a lab that specializes in automotive lubrication, like Blackstone Labs:

http://www.blackstone-labs.com/

Its simply $22.50 for a normal analysis, but I recommend spending the extra $10 on top of that to get the TBN report, which will tell you exactly how worn out the engine oil is.

I've used this several times on my 2007 Nissan Altima during the break in process to let me know how the engine was doing during that very critical stage in its life. I actually have 4 more samples I need to send in and get tested from the past two years on that car, and that will happen soon enough.

If you want to know when you should change the oil, sending in a sample is the best way to know for certain. Its cheaper than an entire oil change, less than a third on this car. You grab 4 ounces of oil, put it in the bottle, seal it up, mail it in, and within a week, you get a full report on your engine. You can then either keep going for another 3k miles, or make an appointment with your dealer to get the work done.

Hope you have a great time with your car.

BC.