Recently purchased a cat 416c. 4 wheel drive doesn't work, which renders it just about useless. When I lift machine off the ground and engage drive all 4 wheels spin, however when any resistance is put to the front drives they stop. I checked tran fluid and it is slightly overfilled... checked all fuses. Not sure how this system works just yet but seems as if it has a clutch in transfer case which isint working. Anyone had this problem? Is it common? Are there any other major issues with the 416c that I should be aware of? Any help will be greatly appreciated as it is winter and work is slow, Cat dealers service out of question for time being...