Combines Rear wheel assist How do they work on 4400 Please explain

Hogfarmer, Get rid of the 4400 and get a combine with RWA, will be better off in the long run. Gg

To my knowledge, you must have the hydro to add rear wheel assist. Basically, oil that goes to the hydro is split and a portion of it goes to the motors in the Mud Hog.

4400 had gear transmission only hydro was not avaliable.

It will require alot of math. Depending on the output speed of the shaft comming out of the trans, the rolling radius of the main drive tires, the final drive gear ratio (standard and heavy duty final drives have different gearing). Then you have the rolling radius of the rear tires and the gear ratio of the rear axel used. Then its a matter of putting a gearbox between to get the drive speed in feet_min of the rear tires to be just faster than the front tires by a few percent. The steering tires must run faster to allow steering. This system could only be in gear while in the field. If you went down the road the drive would wind up untill something broke.

Then Am I to assume that the Mud Hog units were mechanical drives not hydraulic. I have been considering trying to find one of these units as I have a good 4400 and would like to convert it to 4 wheel drive. Pleae elaborate. Thanks!

I remember a little about them. I never run one, but I seen one on a machine once In a salvage yard in Seikston Mo. This was about 17 years ago. I Think you had to run in a certain gear, and they had some kind of mechanical linkage to disengage when you stepped on the clutch. It was hydraulic driven. And was told not the easiest to use and keep adjusted. Joe

The only ones I have seen are mech. It would be impossible to make a workable hydro system without changing the trans input to a hydro drive. That would require mounting a variable disp pump off the engine drive and some machine work to get a high speed hydro motor to mount to the trans input. It would get very expensive. I've thought about doing this but It would cost more than 3 times what the combine is worth.

i saw some used in mich. that were hydro. ran a pulley on the end of shaft under the seat to a hydro pump .i think they were a ''mud hog'' kit

I can't imagine how a hydro rear wheel assist would hold up with a mechanical front drive. The hydro would always be faster or slower than the mechanical drive. Maybe they had some valving set up to let the rear wheels idle along and only drive when the combine slowed down due to the front slipping. I almost think by the time you would have bought such a system a person could have just gone ahead and make the trans a hydro drive, then the whole combine would be hydrostatic drive.