mfwd vs 4wd

dex3361 · Apr 22, 2011

jenkinsph said:
As far as Deere tractors are concerned most of the new stuff is mfwd in the compacts you referenced. FWD can also mean hydraulically assisted front wheel drive such as in my x749 mower. In turns the fwd can speed up the outside front wheel to help reduce scuffing the lawn. Some of the older ag tractors we have (Deere 3130LS) have hydraulic front wheel drive and are fwd but as explained are not mfwd.

For most uses mfwd is the better and more simple way to go.

Does the x749 have wheel motors of a hydraulic motor driving the input shaft to the front axle?

jenkinsph · Apr 22, 2011

dex3361 said:
Does the x749 have wheel motors of a hydraulic motor driving the input shaft to the front axle?

x749,
It has a hydraulically driven front axle with a variable proportioning valve to feed the left and right wheels. The variable valve is connected to the steering linkage so that as the linkage moves left and right this in turn can vary the wheel speeds.

On the older fwd Deere's these had front hydraulic wheel motors to drive the wheels. Don't know how these were made to slip but would guess the relief pressure were set low enough to allow for some slippage.

dex3361 · Apr 22, 2011

jenkinsph said:
x749,
It has a hydraulically driven front axle with a variable proportioning valve to feed the left and right wheels. The variable valve is connected to the steering linkage so that as the linkage moves left and right this in turn can vary the wheel speeds.

On the older fwd Deere's these had front hydraulic wheel motors to drive the wheels. Don't know how these were made to slip but would guess the relief pressure were set low enough to allow for some slippage.

Thanks for the info.

V1Rotate · Apr 22, 2011

Jenk,
I'm a little confused. Does the 749 have one hydraulic motor that drives the front or two?

beppington · Apr 22, 2011

Maybe somebody can explain my 4WD.

Recently when trying to pull down a tree with 4WD engaged ... tree was barely budging, but I decided to keep pulling for a bit to see if it might go ... I observed the front right wheel spinning (trying to pull), but not the front left wheel at all. FLW just sat there. The wheels were turned slightly to the right at that time.

I noticed that if I turned the steering wheel to the left some, sometimes that would cause the LFW to also spin (try to pull), but this action didn't seem to be "firm" ... With the wheel turned to the left, the LFW didn't always "try", just sometimes.

Sometimes neither would spin, & definitely the FRW would spin more often than the FLW. Occassionally both would spin. Occassionally neither would spin.

Is there a differential in the front axle?

Just curious how it works.

dex3361 · Apr 22, 2011

beppington said:
Maybe somebody can explain my 4WD.

Recently when trying to pull down a tree with 4WD engaged ... tree was barely budging, but I decided to keep pulling for a bit to see if it might go ... I observed the front right wheel spinning (trying to pull), but not the front left wheel at all. FLW just sat there. The wheels were turned slightly to the right at that time.

I noticed that if I turned the steering wheel to the left some, sometimes that would cause the LFW to also spin (try to pull), but this action didn't seem to be "firm" ... With the wheel turned to the left, the LFW didn't always "try", just sometimes.

Sometimes neither would spin, & definitely the FRW would spin more often than the FLW. Occassionally both would spin. Occassionally neither would spin.

Is there a differential in the front axle?

Just curious how it works.

You have and open differential in the front end and it will allow the wheel with the least traction to slip if pushed to the traction limit. If the traction limit is not met the power is to both front wheels. The back axle is the same until you engage the differential lock this would lock both axles together and both wheels pull even is 1 is slipping.