My 4300 sync reverser has developed a problem with the low range shifter (1-4) not staying locked in gear. All the gears work fine if you hold the shift lever in place but when you let go it may go for a little while and then it jumps out of gear and into neutral. From what I have found out so far there seem to be some spring loaded detents which hold the actuator in a certain gear. Does anyone have any experience with this and know whether it may be possible to attempt a repair myself?