JD 344H Wheel Loader - Back wheels will not engage.

[SHeimes]

We have a 2000 JD 344H wheel loader new to us for 6 months. Everything was working fine until the recent snow storm. Only the front wheels will spin when pushing snow, making it almost impossible. Is there a lever or solenoid that would disengage the rear end? Or, did something happen in the rear end differential? There is no grinding noise coming from the rear. Spline shaft strip? Lock washer/nut wiggle loose?
Thanks

 

[JRsEquipment]

Something broke, the transfer case mounts directly to the rear axle and is direct drive to the rear(no drive shaft) or no disconnect as far as I know. So I would guess something broke in the transfer case or in the rear axle. I would drain/check oil in rear axle and transfer case for metal.

 

[Nige]

I'd have a look in the rear axle first, but if it has broken an axle shaft there may not be a lot in the way of metallic debris.
Follow that by disconnecting the drive shaft between the transfer case and the rear differential at the diff end, jack up the rear end until both wheels are off the ground, then turn the differential pinion flange so see if one or both rear wheels turn.

 

[JRsEquipment]

It has no rear drive shaft, the transfer case is direct mounted to the rear axle and has a drive shaft to the front axle. the output from transfer case is direct into pinion of rear axle it is integrated as one. You are correct if it is a clean break it may not have any metal but still worth a look, it also has a planetary at each wheel and the input shaft or gears in there could break as well.

 

[Nige]

My bad, assumption is the mother of all f**k ups.........
In that case what about jacking up the rear end so that both wheels are off the ground and rotating one wheel.? If everytrhing is working as it should then surely the other wheel ought to rotate in the opposite direction.? That is unless the RAX has a Detroit Locker in it.........

 

[SHeimes]

How big of a job am I getting into? It looks like I need to remove the direct drive or gear case from the pump and rear axle, then possible pull both rear wheels off and remove the axles or hubs to get access to the transfer case. None of these items excite me.

 

[Nige]

In that case what about jacking up the rear end so that both wheels are off the ground and rotating one wheel.? If everytrhing is working as it should then surely the other wheel ought to rotate in the opposite direction.?

Have you tried this suggestion.?

 

[SHeimes]

So I was able to jack up the rear end. I can spin either wheel and the opposite wheel does nothing. I was able to view some of the gears from the back side of the transfer case and nothing is moving when I spin the tires.

 

[Nige]

So I was able to jack up the rear end. I can spin either wheel and the opposite wheel does nothing. I was able to view some of the gears from the back side of the transfer case and nothing is moving when I spin the tires.

I see some disassembly in your future..........
At best it's broken an axle shaft, at worst the diff could be toast.
Are there any magnetic plugs on the rear differential housing or the final drives.? If so, have you inspected them yet.?

 

[Hyperpack]

I have the same loader and it had the final drive planetarys repaired several times before i got it. In my opinion they are very small compared to most others in that HP and weight class. I would suggest take a rear wheel off and remove the cover of the outboard planetary and look for damage then check the other if the first looks ok.
Hyperpack