What was burning up in your undercarriage? What kind of day to day maintenance did you do to your undercarriage? I have a Cat 257 that I bought last December. Most of the hours I have logged on it have been snow removal hours. I love the machine in the snow. Pushes everything I ask of it, pushes up hill, and rarely slips. Plus it is easy on the lawn when I am pushing piles over. I have talked to a lot of CAT MTL owners in the area and no one seems to have major track issues. The undercarriage is complicated but a simple cleaning after every use will save you $$ in the long run. Keep the tracks cleaned, don't allow for stuff to build up and allow for a little extra care/caution when operating in conditions that might chew up the tracks.