The splines on the input shaft are worn almost to stripping point.
The local dealer says that the pinion (and crown wheel) are discontinued. They aren't discontinued according to the US parts websites but I can't order from US due to Kubota regional restrictions (and price is eye-watering).
1. Can anyone offer help with sourcing a new or good used pinion and crownwheel? [Edit: M4500DT - same pinion as M5500DT and M7500DT - bevel pinion part no 36280-42262, superseded by 36280-42240]
2. The original parts book listed the pinion and crown wheel separately so I wonder if it is possible given low speed of these machines that the pinion can be changed out without requiring a change to the crown wheel - does anyone have experience with that on tractors?
3. The pinion gear and bearings (in fact the whole diff - except for oscillating trunnions) are in perfect condition, does anyone have experience with reconditioning splines? One posting I saw suggested machining the worn splines off to a hex (smooth radius the transition from end of hex to round shaft) and shrink fitting a splined outer section on.
Whatever the solution, it needs to be reliable because I need the front wheels for braking on our hills
[Edit: the same pinion is used in the 80 hp M7500DT as my 55hp M4500DT so some modding might be OK...]
The cause of the spline wear? I think it's because the trunnion bearings wore long ago, were reconditioned and bushes replaced, but the reconditioner forgot to include grease, or left out a couple of O ring seals (hence the rust), so the trunnion bearings wore out again (they don't have grease nipples). This caused the pinion shaft to move out of correct alignment with the propellor shaft, so the coupling between propellor shaft and input shaft had to become self-aligning... which it did by wearing away the splines on the input shaft and in the coupling...
Thanks in advance for any help/experience you can offer.
The local dealer says that the pinion (and crown wheel) are discontinued. They aren't discontinued according to the US parts websites but I can't order from US due to Kubota regional restrictions (and price is eye-watering).
1. Can anyone offer help with sourcing a new or good used pinion and crownwheel? [Edit: M4500DT - same pinion as M5500DT and M7500DT - bevel pinion part no 36280-42262, superseded by 36280-42240]
2. The original parts book listed the pinion and crown wheel separately so I wonder if it is possible given low speed of these machines that the pinion can be changed out without requiring a change to the crown wheel - does anyone have experience with that on tractors?
3. The pinion gear and bearings (in fact the whole diff - except for oscillating trunnions) are in perfect condition, does anyone have experience with reconditioning splines? One posting I saw suggested machining the worn splines off to a hex (smooth radius the transition from end of hex to round shaft) and shrink fitting a splined outer section on.
Whatever the solution, it needs to be reliable because I need the front wheels for braking on our hills
[Edit: the same pinion is used in the 80 hp M7500DT as my 55hp M4500DT so some modding might be OK...]The cause of the spline wear? I think it's because the trunnion bearings wore long ago, were reconditioned and bushes replaced, but the reconditioner forgot to include grease, or left out a couple of O ring seals (hence the rust), so the trunnion bearings wore out again (they don't have grease nipples). This caused the pinion shaft to move out of correct alignment with the propellor shaft, so the coupling between propellor shaft and input shaft had to become self-aligning... which it did by wearing away the splines on the input shaft and in the coupling...
Thanks in advance for any help/experience you can offer.
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