JD 4840 Powershift Problems

JD 4840 problem Problems

I’ve been spraying a lot with my JD 4840 and I noticed today as I was moving down the road that 8th gear doesn’t want to pull the hills and when I got down to 7th I lacked ground speed. The tractor downshifts fine, but when I upshift it doesn’t give me that jerk I’m used to feeling. I have checked the transmission / hydraulic fluid and it was fine and the transmission light never came on. The brakes have been grunting a bit lately. Could my filters be clogged with pieces of brakes? Is there anything else I can check before calling my mechanic?

  • If by “does not want to pull the hills” do you mean that the trans is slipping? Definitely change the filters, and if you know the brakes are on the way out you may want to drain the trans and clean the crankcase screen. After that you will have to check the pressures. If they are all goo my next guess would be the slip clutch that absorbs the shifts from the powershift (not sure what it’s called, but not the traction clutch.)
  • I suspect the dry-drive clutch on the flywheel is worn and damaged. Put it in the upper gear with the clutch depressed, 3/4 + throttle press hard on the brakes and release the clutch. The engine should stop. I suspect it will slow down before it dies, suspecting that the clutch is slipping.
Farm Center
Add a comment