Komatsu D20 steering problems

I am looking for information about a steering problem I am having on my D20. While going forward, the left clutch and brake work fine, but the right clutch disengages and the brake doesn't fully apply to stop the track. When I am in reverse, both clutches disengage and the brakes seem to only grab when the steering lever is pulled fully rearward. It is hard to "feather" the braking action.

I just bought the machine and everything was working fairly well until today. The brakes were a little touchy but managable. Could it just be out of adjustment? I do not have any slippage in the drive train and the steering clutches are not chattering when they are engaged or released.

I would also like to know the adjustment procedure for the shifting brake. I was told this machine has one and mine seems to need adjustment.

Any tips or tricks would be greatly appreciated as I am not new to working on my own equipment.

Thanks, David

Very easy dozer to work on. I do not have a manual but was able to figure out the assembly process. A little tricky but managable.