Pump gear what if?

[sparkycuda]

I believe the gear material has more to do with longevity and wear than performance, if all dimensions of pump housing, gears, tolerances, etc. are equal. Hydraulic pump efficiency is determined by measuring flow (gal/min, cc/min, etc)) at no pressure and then again under rated pressure: pressurized flow rate divided by free flow rate = % efficiency. Gears pump should be 85% or higher. If lower, it indicates that oil "slippage" is high - internal tolerances are beyond acceptable standards - you will see slow movement and/or low pressure when working and extended operation may cause oil heating.
If you want to test the pump, have a calibrated container to pump into. Fill the supply reservoir and run the pump at rated RPM for a specific time (maybe 30 or 60 sec). Measure how much flow was delivered at no pressure. Repeat the test but have a valve and pressure gauge in the output line. Run pump at same RPM as first test, but slowly close the valve until gauge indicates rated pressure of the pump, then collect and measure oil volume over the same time period as first test. A bit complicated but you will know what the pump is doing. If badly worn, pump may not be able to produce the rated pressure.
Note: while the system is still in your machine, be sure to verify the relief valve is functioning properly. You should be able to adjust and see if the performance changes. If you cannot adjust pressure, maybe the valve is defective or stuck. Does your machine have a pressure gauge on it? If yes, what pressure does it show when a cylinder gets to end-of-stroke?
If the pump tests OK out of the machine, something in the rest of the system may be at fault.