If it were me, I'd keep the 4runner. New tires and a 90k service do not cost as much as a brand new rig. If your current rig does the job without any complaints, why fix what's not broken?
I guess I'm a little biased though. My Lexus(toyota) daily driver has been nothing short of phenomenal. 134k miles in under 5 years, and the most expensive repair I've made on the thing was a couple of o2 sensors. Come to think of it, that's the only repair I've had to make.