If we are talking cylinders here. you do realize that the pump is not putting out full pressure at all times. If he is lifting an empty bucket, he is probably only using less than 1000 lbs. You can only achieve the max pump pressure when you are at the max load the system was designed far,. For instance, If the tractor has a lift capacity of 1800 lbs. at 2500 psi, the relief is probably set at around 1800 to 2000 psi. If you lift half a bucket, I don't think you will see 2500 psi. Put a gage on your lift cylinders, and see what happens in different situations. My PT, say at half throttle, may raise the bucket up one foot. If I increase rpm, it starts to lift more for whatever reason . Last year, I had to change out my lift pump, because it could not raise half a load. After I installed the new pump, the max load went right up like it should. I was either losing pressure, or volume, or both. You will not get max pressure or volume at low rpm. If you load it up, then you may see anything up to max pressure.
He might also have some leaky cylinders, or a pump that is not putting out max capacity.
New recommendations.
1 Check psi and GPM on your pump. Check pump psi with gage. Hydraulic shop can check GPM.
2 Adjust relief as you desire.
3 Larger cyl will definitely give you more power. You may have to add more counter weight.
4 Take the bucket off, add a lifting attachment. That will save about 150 to 200 lbs
If talking 3PH, forget what I said about the cyl. The first two only.
