Komatsu D37E-5

I've been looking to buy my first dozer for about two years now. I have 73 acres of timber with lots of ravines and draws and a creek that runs about 8 months a year. The previous owner had the pines logged in 1994, but the hardwoods are virgin. We had pretty bad drought conditions over the last 6 years that have killed hundreds of my red oaks, and a few of the hickories. I want a dozer for road maintenance, and to build a couple of new roads. I would also like to build a couple of small ponds (1/2 acre or so) and clear the small trees and underbrush from about 15 acres around the house. I built my house back in the woods in a 3 acre clearing I made with a rental dozer (D5N), so I understand the limitations of taking out larger trees with an undersized dozer. My question is about a Komatsu D37E-5 with a 6 way blade. I have found one with a complete new undercarriage; sprockets, idlers, rollers, rails, and pads. The machine has 8100 hours and smokes white when you first rev it up. No visible seepage anywhere. Lift cylinders just rebuilt, and all new trunions and ball joints on the blade. What should I worry about on this machine? Any Komatsu guys out there who can give me some advice? I'm an old farm boy, but I know nothing about maintaining a track dozer, and even less about Komatsu's. Thanks, Lynyrd