With synthetic oil 10K oil changes are conservative. You can probably go longer. I've been doing 10K on my 2007 Tacoma since new. I'm at 202,000 miles now with no oil consumption between changes. I do the same with my F150 and Honda. They have well over 200K combined.
There are lots of guys over at the Tacoma forum with over 400K on their trucks that used 10k intervals. There is a guy in NC who got 880,000 out of his 1st engine with 10K oil changes. It was still fine internally, but needed a new head gasket. Rather than repair the old engine he bought one from a scrapyard with 100K on it. He is over 1.3 million miles now and still changing oil at 10K. Actually, he doesn't change at a certain mileage, just once/month. But he averages driving 10,000 miles each month.
That's fine, but I just changed my 2004 Taco oil after 7,000 miles (230,000 on the truck now) and that chit was old and smelled bad (mobil1 full synthetic). I generally change it every 5,000, but got lazy and let it go. The engine was not running or sounding as smooth as normal, so I wanted to change it. After the fresh oil, it's smooth and quiet like it should be. I don't trust mine running more than about 6,000 miles, but that's just me. No need to wreck an engine and changing it every 5,000 isn't going to hurt it... I also agree that it depends on your driving habbits. I drive mine like I stole it, not like I'm driving miss daisy....
