There is a tech tip out on dealerlink re rear wheels not turning on the larger M series tractors in cold weather. We have had a couple of instances of this, one just this weekend. the fix seems to be changing the brake fluid annually to remove any moisture trapped in it. this is recommended in the operators manual but who reads that? The tip is only listing the powershift tractors but it could apply to all with hydraulic brakes. the powershift tractors and the M---40 series use UDT for brake fluid but some of the older M's use DOT brake fluid. Be careful! Be sure you use the proper fluid in there!
Ed
Ed