Thanks! If your tractor is tier4 have you seen any issues?

But the 540E does work at the engine peak torque, give or take a couple RPMs.
I guess I did not explain torque rise sufficiently. Here's a much better explanation: Perkins | Torque backup
My 3725's tach "green zone" is 2000-2500 rpm. That's where the manual says you're supposed to run it to keep the DOC+DPF happy. So I don't use 540E. For my pto tasks I wouldn't use it anyhow. The chipper needs all the power it can get. 95% of my mowing is on hills where I need full power to drive uphill while running the mower.
Some of my mowing is on steep hills, like along my driveway. Yesterday I used the grapple to carry a heavy log up the driveway to my house. The log was heavy enough that the loader would not curl it up all the way. I had to put the tractor in low range. And I have smaller than normal tires for this model hence slightly lower gearing.
One drawback of running at 1900 rpm is that you don't get "torque rise". That's where torque increases as rpm decreases from normal operating rpm, as long as rpm does not get too low. Most tractor engines including ours are set up that way. For example here's power curves for the A1700:
View attachment 647622
Note the torque peaks at about 1800 rpm, but HP is highest at peak rpm. (The bottom SFC chart is specific fuel consumption or fuel used per HP. Running in 540E would result in lower fuel use).
Hi Eric. I don't want to hijack the thread but I don't want to start another one either. Which chipper do you have and how would you describe your satisfaction with it? What size/type brush are you chipping?
I have a Woodmaxx 8H 8" hydraulic feed chipper. I had a hard time deciding between that and the Woodland Mills. Both are North America designed and built in China and about the same price. They're different designs, there are plusses and minuses to each one. I watched a lot of videos and it looked like getting sizeable material to start feeding is more work with the Woodland Mills. I'd have to run them side by side to really know though.
I have about 10 acres of land that was pasture in the '40s and has been left since then. There's a lot of coyote brush, some coffee berry, and trees (bay, fir, tan oak) ranging in size from small to 40'. Most of it is coyote brush though. Very mature coyote brush. Some of the trunks are too big to go into the chipper. And poison oak too, but I don't chip that.
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