I got a B7100HST 4wd. I changed the transmission filter and fluid. Now the control operates in reverse when pushing down on the forward end and forward when i push down on the rear end. The only thing I can think of is the dealer gave me the wrong filter as nothing else was changed, no hoses removed and it worked normally before this, what did I do? I dont want to put the old filter back on as it's very dirty. Any ideas? Nobody else seems to ever have this problem. Any ideas?