1999 expedition eddie bauer how are they

I just picked up a 99 expedition for really cheap 2500 bucks.. It has a alot of miles on it though.. 131k.. but runs great.. How long will the motor, tranny and transfer case last. Do i have to worry about any of these going anytime soon ? He just had some sensors replaced in the transfer case and the oil changed.

My 99 Eddie Bauer has 192,000 and the Triton 5.4 V8 and tranny are still going strong. Proper service is the key!
Ron