I don't own a 4Runner, but I've been keeping a friend's '99 3.4 2WD on the road for the last 5 years. It has 286k miles on it.
I've used this site a lot for help, so I thought I'd register and make it official. T4R.org has helped me tackle a rear axle seal, timing belt/water pump/front crank seal, AC compressor/receiver, lower ball joints (returned the Moogs and got Toyota parts after reading posts), and power brake booster (replaced with a Toyota booster pulled from a junkyard instead of going with a reman unit after reading posts).
Thanks for all the help - I hope I can return the favor.