Make sure you have access to your tractor serial number, because there is a chance that the John Deere 6125D parts you need depend on that serial number. Usually, the serial number is printed on the right side of main tractor frame above front axle. They also have mechanical wet disc brakes. The type II 3-point hitch is very reliable, capable to lift 7,649 lbs [3469 kg]. It is used with a mechanical lower link. It is also worth noting that the independent rear PTO runs at 540/1000 (1.375) rpms. The John Deere 6125D has an open center hydraulics system with a 15.3 gal [57.9 L] capacity. The pump does the job pushing 17.6 gpm [66.6 lpm] fluids in the hydraulics system.