Need Help with my Cat e120b

I have a 90's Cat e120b. Both of the track motors have no power and it can't steer or go up hills. From what I've seen from my research is this could be a swivel seal. Does that sound right? Thanks,
Josh

I have an E110B it does not have a lot of power when hot. I have to help it turn with the boom. If you don't have an oil leak underneath, I would not think it was the swivel. Mine has a lot of hours on it and it still trns when cold. I would check pressures first. The manual is expensive, but worth it. Get the original too, those copies just don't cut it. I got mine from Cat. I need to remember where I put it!!!