Just my opinion...
A Porsche 911 turbo's factory recommended oil service interval is 15k miles. I don't know about you guys, but I wouldn't ruin a $140k car.
Think of it this way...
Our warranties expire at 3yr/36000 miles. I think power train is at 5yrs/50k. Do you think Toyota will repair/replace your engine if it fails at 55k miles?
The point of all of these extended oil service intervals is to show how little maintenance costs on newer vehicles and to sell more of em. For example, I am a government body looking to replace my fleet of police cars. The Chevy Impala says I don't have to change my oil for 15k miles. The Ford Crown Vic says 5k miles. The Impala doesn't have to service the trans for 100k miles, while the Crown Vic is at 30k. It looks like the cost of maintenance will be considerably cheaper if I buy the Crown Vic. Wow! looks like Ford just sold 200 Crown Vic to your local police dept.
And for those of you that "do" your own l services... More power to you. I hope you take the time to inspect your brake linings, lube door hinges, grease all necessary fittings, check all lights, test your battery, check air filters (both of them, if you don't know what the second one is- you shouldn't be changing your own oil), resetting your maintenance light, etc. You should at least go out and buy a grease gun and hit those fittings (if you know where they all are).
How much money are you really saving if you change your oil every 10k vs. 5k? Let's see, $80 per oil service at an average of 15-20k year in mileage.
10k service is $160/yr
5k service is $320/yr
For a savings of $160/year.
My opinion...cheap insurance for our $30-$40k trucks.
Sorry guys, just venting! Sometimes it blows my mind that we put so much money into customizing our beloved trucks, we overlook such simple things.