No Rear Wheel Drive on KM454

Scozz · Jun 29, 2008

Well, while fixing one problem I've created another one. I was working on diagnosing the lack of steering on MY KM454 and using the split brakes to steer the tractor while moving it to the pressure washer. I believe the diff lock was still locked while I applied right brake while backing up. I heard a "snap" and the tractor stopped moving. I have no drive in forward or reverse. Tractor works when put in 4WD. I'm hoping there may be a shear pin that did its job but I didn't see anything when looking in the parts book. Any Idea where I should start? Thanks .... Scozz

RickB · Jun 29, 2008

I don't know anything about your tractor, but if it has bull gear final drives, I'll bet lunch you have snapped one of the differential half shafts, or bull pinion shafts, whichever you choose to call it. In fact, if it has planetary final drives, you have broken a differential half shaft or sun shaft, whichever you want to call THAT.

Scozz · Jun 29, 2008

Rick thanks for the speedy reply! It has Planeary final drive. I was thinking that it may be something in the shaft assembly, not that I'm much of a gear head. It makes better sense that it would be in the final drive. ... Scozz

greg_g · Jun 29, 2008

Fortunately I've never been in a position to take the hydraulic sump off my KM454. But your problem got me to lookin' in my parts manual. After considering the brakes versus diff lock scenario, I think I'd direct my initial attention to the vertical pin on which the planetary gears revolve (part 16 on pg79), then at the driveshaft (part 33 on pg77) that actually engages those planetary gears

//greg//

3RRL · Jun 29, 2008

Did you happen to try putting it back with differential lock on in 2wd to see if it moves?
If it is a half drive shaft that broke, you can determine it that way and also which side.
If it still doesn't move, then Greg is on to something with part number 16, I believe.

Scozz · Jun 29, 2008

Yeah I tried that ... no good. My parts breakdown must be different than yours cause the pages and # don't match. Are you talking about the "planetary shaft"? ... Scozz

greg_g · Jun 30, 2008

Yup. #16 on the Differential Assembly page is part number 450.37.183 Planetary cone gear shaft. I believe #33 on the Shaft II Assembly page (450.37.101) is the shaft that engages those planetary (cone) gears.

//greg//

Soundguy · Jun 30, 2008

If it won't pull in diffy lock / 2wd.. I wonder if it could be a pinion shaft driving the rear end. ( i have no diagram of this rear end.. just thinking out loud in general terms.. )

Can't wait to see how this one pans out.. good luck to the original poster.

soundguy

greg_g · Jun 30, 2008

Soundguy said:
.. I wonder if it could be a pinion shaft driving the rear end.

No pinion. The diff lock consists of a large barrel type fiitting with six protruding pins. It's part of the non-drive axle. The diff lock lever slides that fitting laterally so it mates with six holes on the actual differential (which is obviously connected to the drive axle)

//greg//