knuck, knuck on JD3720

Deere Dude · May 31, 2011

Maybe one of you can shed a little light on my 3720. I get an audible knucking sound when idling, wheels turned to right or left, Idling so I can hear easier. Wheels straight, it seems fine.I tap the hydro pedal to go forward or reverse, and let off the pedal I hear a sound that comes from the frame section someplace. I don't ever remember hearing that before.

It is a 2010, 3720 with 125 hrs. I checkerd the lug nuts and they are tight. I dion't see any loose hardware. I took the loader off, the 3 point attachment off. I took the top link off. I tied the 3 pt. lift arms together with a bungy cord. I looked underneath and don't see any loose stuff. The only thing that wiggles is the drive shaft for the front end. Boy is that thing whimpy, by the way.

If anyone else has noticed that on yours and know of a fix, please let me know. It's under warranty yet and if I don't find an easy fix by tomorrow I'll have to take it to the dealer. Thanks in advance,

JDGreenGrass · May 31, 2011

Deere Dude said:
Maybe one of you can shed a little light on my 3720. I get an audible knucking sound when idling, wheels turned to right or left, Idling so I can hear easier. Wheels straight, it seems fine.I tap the hydro pedal to go forward or reverse, and let off the pedal I hear a sound that comes from the frame section someplace. I don't ever remember hearing that before.

It is a 2010, 3720 with 125 hrs. I checkerd the lug nuts and they are tight. I dion't see any loose hardware. I took the loader off, the 3 point attachment off. I took the top link off. I tied the 3 pt. lift arms together with a bungy cord. I looked underneath and don't see any loose stuff. The only thing that wiggles is the drive shaft for the front end. Boy is that thing whimpy, by the way.

If anyone else has noticed that on yours and know of a fix, please let me know. It's under warranty yet and if I don't find an easy fix by tomorrow I'll have to take it to the dealer. Thanks in advance,

I had a noise up front on my 770 when turning. Thought it might be the power steering cylinder but, what I found it to be was the center pivot grease fitting on the front axle.

Don't know if the 3720 has this type of fitting but, it may be worth a look.

Also, try posting in the Deere Forum here at TBN.

retiredmgn · Jun 1, 2011

Deere Dude said:
Maybe one of you can shed a little light on my 3720. I get an audible knucking sound when idling, Thanks in advance,

Not quite sure on this. While 'knucking' is the 'k' silent?

whodat526 · Jun 1, 2011

does it happen when u turning the wheels are after wheels are turned because i had a popping should before on a 4wd massey in the frontend and it was the grease fitting in the pivot pin where the plantery drive connects to the main section that was in need of some grease after i greased it the noise went away

Deere Dude · Jun 1, 2011

whodat526 said:
does it happen when u turning the wheels are after wheels are turned because i had a popping should before on a 4wd massey in the frontend and it was the grease fitting in the pivot pin where the plantery drive connects to the main section that was in need of some grease after i greased it the noise went away

The wheels are turned most of the way in either direction, and then I tap the hydro enough to move the tractor a foot or two, it makes the knucking sound, and then the same thing happens in reverse also. I'll check around for grease fittings.