ok i took my truck mudhogging a few day ago. when i shifted out of 4wheel back to 2wheel and backed up a few feet it acted kind of like it stayed in 4 but its not i checked for sure its in 2 cause i can powerbrake it and the front wheel wont turn. so when i went to put it in reverse it feels like its just sipin and barely moves the truck. i can feel something like jerking when i push the gas to backup. what could this be?