4310 drive line clunk when in 2WD

Mike_ONeill · Jul 5, 2020

Tractor is a 2003 model 4310 eHydro.

Especially when turning, it sometimes feels like it is in 4WD when I have 2WD selected, then I will hear a clunk noise and feel a slight jolt. I suspect the MFWD is not fully disengaging and the jolt/clunk is when it lets go. This happens often, even if 4WD has not been used for a while. The issue seems to be gradually getting worse.

The cylinder that disengages MFWD has about 3/4" stroke, which doesn't seem like much. I removed the pin joining the cylinder to the lever, and can easily move the lever about twice as far in the "disengage" direction.

The tractor was split open early last year by the dealer to replace a broken range shift fork. I don't know whether that has anything to do with it.

What should the stroke of that cylinder be? Any other ideas?

Thanks

joecdeere · Jul 5, 2020

remember ALL the front drive systems turns regardless of whether the 4WD is engaged or not, you might jack up the front end and turn both the front tires by hand and see if you feel anything. You could have a bearing or gear failing in the final drives.

Zebrafive · Jul 6, 2020

A clunk sounds like a U-joint. Check those too.

beenthere · Jul 6, 2020

Zebrafive said:
A clunk sounds like a U-joint. Check those too.

I looked for one on the 4310, but didn't find it on a quick glance.

jgayman · Jul 7, 2020

beenthere said:
I looked for one on the 4310, but didn't find it on a quick glance.

This what is shown for the front drive shaft.

beenthere · Jul 7, 2020

What I found too. A place to start looking for the "clunk".

Zebrafive · Jul 8, 2020

Is it possible to remove the driveshaft without an oil leak from either the trans or front axle? If so, that might help to find the clunk, when jacking up the front and turning the tires by hand.

Mike_ONeill · Jul 9, 2020

Thanks for the replies. Front wheels and driveshaft all turn smoothly by hand.
The local Deere service manager could find no specs on what the stroke of that cylinder should be. The Deere technical manual doesn't give it either. It appears to be a spring-return single acting cylinder. The second port on it is low pressure and looks to be a return line for any leakage past the piston.
I removed the pin linking the cylinder to the lever and turned the driveshaft with one hand while holding the lever with the other. Could feel the spline teeth of the shift collar starting to engage with the lever right where it would be with the cylinder extended (2wd position). The yoke is threaded to the cylinder rod.
So I turned the yoke one turn in the extend direction, locked the jam nut, and it seems to be fixed.

arlen4720 · Jul 19, 2020

Mike_ONeill said:
Thanks for the replies. Front wheels and driveshaft all turn smoothly by hand.
The local Deere service manager could find no specs on what the stroke of that cylinder should be. The Deere technical manual doesn't give it either. It appears to be a spring-return single acting cylinder. The second port on it is low pressure and looks to be a return line for any leakage past the piston.
I removed the pin linking the cylinder to the lever and turned the driveshaft with one hand while holding the lever with the other. Could feel the spline teeth of the shift collar starting to engage with the lever right where it would be with the cylinder extended (2wd position). The yoke is threaded to the cylinder rod.
So I turned the yoke one turn in the extend direction, locked the jam nut, and it seems to be fixed.

View attachment 662710

Check the front trunion thrust bolt. They cause clunking when they loosen up, the the whole front axle slides back and forth

beenthere · Jul 19, 2020

arlen4720
You may have a good call on that trunnion thrust bolt. Reminded me of a similar clunk when that adjustment bolt was loose in my 4300..
Key # 31 bolt and locking nut #8

There are two, for and aft of the axle.