The greatest damage to any new ring & pinion gearset commonly occurs during the first few hundred miles while the gears are bedding-in. If driven hard, you will overheat and damage to the gears. This is because the surface finish of the gears are not perfectly matched and need some run-time to bed the gears to their match. Even though the new ring & pinion gears are lapped in they still must have sufficient run-time to allow the contact pattern to properly develop. 

Over the course of a few hundrd miles the gears will bed-in, increasing the load bearing surface area which improves the overall durability of the gearset. It takes much longer than you think for the EVO transfer case gears to bed-in and the longer you can wait before kicking it's ass the better.

Recommend procedure for breaking-in your new ring & pinion:

Follow the transfer case filling instructions provide on the FAQ section of this site. Vehicle speeds should stay below 60 mph for the first 100 miles. Drive the vehicle 10-20 miles, stop and let cool for 30 minutes.Do not abuse or dump the clutch or do any hard acceleration as let the ring & pinion bed-in gently. If you take it easy on a new ring & pinion and perform regular oil changes it will last much longer. Use caution when letting out the clutch as aggressive high rpm clutch dumps can fatigue parts and may lead to eventual failures.

New or recently rebuilt transfer cases should have the oil changed after the initial first 500 and again after 1000 miles.  TRE adds a Moly assembly additive to transfer case, do not be alarmed by the color of the oil.  Vehicles that are being road raced require race car maintenance and all drivetrain oils should be inspected after each race and changed if the oil is dark or stinky. Road racing applications may add an additional 1/2 pint of oil to the transfer case for added lubrication and cooling.

Transfer case oil recommendations