I have a Cat HM312 on a 287B MTL .When doing first cut, keep the door in the front of the mulcher completely open. If possible chop the tree into as high as possible and lower the arms or curl the bucket arms to chew the lower part of the tree down to the ground. I have found if you cut the tree low and try to drive over it, you must almost always back up. If you go forward, it will spit the tree out behind you some distance. Later, if you want to mulch finer, close the door and run over it some more. Try not to hit anything metal as it will chip the teeth or break them entirely. Brush is pretty easy. Hardwood saplings grouped close together are very time consuming and will easily clog the head if your not careful. If you do hang something in the head, find something hard like a stump and put slight down pressure on the head and back up. You may have to repeat the process if it is jammed really tight.If you have a head with carbide teeth you can cut below ground level and it won't hurt the teeth. If you have steel teeth always stay above ground level. Take the time to stop every once in a while and clean the radiaor. Heat (radiator clogging) in the woods will always be your enemy. Take the belly pan off and clean the bottom end of the machine at least once a year. Also carry a fire extinguisher just in case brush in the belly pan catches fire. Finally, If you every have to change the quick connects, change the male and female at the same time so no leaks. And keep a spare replacement seal kit for the mulching head hydralic motor on hand. It will save you lots of down time. All this knowledge was learned from the school of hard knocks. Hope this helps. Good luck.