Deere 3320 Won't get up to speed

[Big Dog Tractor]

I have a Deere 3320 hydro bought new now has 600 hours. It has started to take more RPMs to run in higher range. Example: RPMs are at 2100 after getting up to speed they drop to 1800-1900. It seems like the tractor just won't go..like it is under a load. This seems to be somewhat intermittent as it may or may not happen all the time or it just fixes itself. Does it when the oil is hot or cold. Have also noticed that the speedometer can be erratic with the numbers being low and bouncing all over the place. Transmission oil looks OK and is full.

 

[DanD78]

Make sure the 4wd is off and the load match is shut off. If I have my load match turned on I loose a couple MPH because the hydro backs off to keep the engine RPMs up. Fuel filter?

Dan