Beginning with the C model, CAT introduced a feature called All Wheel braking.
When the All Wheel Drive switch left side is pressed, you are in constant all wheel drive.
When the switch right side is pressed, the All Wheel Drive is completely off.
When the switch is in the center position, the front axle is engaged when you apply the brakes and this will double the braking ability of the machine.
As soon as you release the brakes, the front axle is released.
This is all done with the all wheel drive solenoid and switches on the brake pedal.
So, it is possible to have the front axle to engage if you were bouncing and the pedals were bouncing too.
The only way to be certain you do not have any damage to the front hub is to fully disassemble it for a complete inspection.
If the oil has always been serviced and was kept at the proper leave, I doubt you have any damage.
I haven't seen any failures of the hubs or final drives without the oil leaking out or water getting into the oil.
If you need further help on this, please let me know. I will be glad to help all I can.