We have a Komatsu D37EX-21, which has started locking the track on one side occasionally. It then requires moving forward and reverse a few times until it releases. I'm thinking something broken in the planetary gears inside the hub, but won't be pulling it down until this weekend. We changed the hydraulic fluid recently and did notice what appeared to be possible fine metal particles in the old hyd fluid. Any experienced suggestions on what would cause the lockup and what else to look for would be greatly appreciated. ID is KMTODO10H01005574 Thanks in advance
I was hoping for some info. I've had an older Michigan apart for seals, but never a locking up problem. Still looking for knowledge if you are familiar with this kind of problem. Thanks
Dump the oil out of the bottom of that final drive and if it is full of chunks of metal, then voila, you have found the cause. Fines do not lock up bull gears unless there is cups full. That would be a good start. Simon C
I took apart the hub. There are particles of metal around the seals and bearings, but no clear source. The short shaft that goes into the drive motor is heavily worn, but all the bearings and gears are smooth and don't seam to be where the metal is coming from. Is the drive motor a normal failing part, and are they serviceable? I don't see anything that should cause a lock up. The track sprockets are badly worn and will be replaced and also Idlers. That also shouldn't be causing a lock up to where the dozer won't move. When it locks up, the track is not out of place and appeared to be in proper position. Also when we drained the hydraulic oil, there were small chips of metal that were found. The hydraulic oil has also filled the final drive assembly full and is leaking into the hub somewhere. Must be through the seal in the drive motor. I cannot find a diagram or breakdown of the drive motor to show what I'm dealing with. I don't see how the hub being filled to the top with oil would effect function. Any knowledge is greatly appreciated.