With that much open area in the cab, the transmission has probably gotten a lot of water in it from rain, etc. through the shift tower. Pull the top cover off and inspect the gears- - - -you might have some serious rust problems inside.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!