Farmall B Narrow Rear Wheels

[KJB34269]

I have researched this and the more I learn, the more confused I get. My B has 11.2-24 rear tires. My tire spread is approximately 81 inches. I do have a trailer with an 84-inch bed so it does fit but I would like more fender clearance if possible. I do have rear weights installed and I would like to keep them. Here is something from AI and I'm wondering if it makes sense and is doable for me. 72 inches would make life easier for me. My tractor is pretty much just a parade tractor.

To set up a 72-inch tread width on your Farmall B with 11.2-24 tires, you do not need to dish the wheel centers out. You will keep the cast iron wheel centers dished inward, but you must swap the rear tires/rims to opposite sides of the tractor. [1]
This specific configuration provides excellent clearance for both your wider 11.2-inch tires and your rear wheel weights. [1]

The 72-Inch Step-by-Step Configuration

1. Keep Cast Centers Dished In: Leave the heavy cast hubs clamped to the axles with the dish curved inward toward the tractor chassis. [1, 2]
2. Swap Tire Sides: You must move the left tire/rim assembly to the right side, and the right tire/rim assembly to the left side. This ensures the directional V-tread of your tires still points forward for proper field traction. [1]
3. Mount to the Inside Loops: Bolt the 4-loop rims to the inside of the cast wheel centers. Because the rim brackets are offset, swapping sides puts the wide side of that rim offset facing outward, pushing the tires out to the exact 72-inch center-to-center mark. [1, 2]

Wheel Weight Alignment for this Setup
Because the cast hubs remain dished inward, your 145-lb wheel weights will sit nested inside the deep bowl of the wheel center facing outward.

• The Benefit: Since the rim loops are bolted to the inside edge of the center disc, the tire carcass is pushed away from the tractor frame. [1]
• The Clearance: Your wide 11.2-24 tires will have over 4 inches of breathing room from the fenders and final drives. This makes it incredibly easy to reach the wheel weight mounting bolts without the tire sidewall bulging into your workspace. [1, 2]

 

[MM-TX]

This is a page from the owners manual. If you don't have one it is helpful.
With 11-2 tires which are wider than original at some point your narrowest settings will rub your fenders.

 

[grandpa Love]

This is a page from the owners manual. If you don't have one it is helpful.
With 11-2 tires which are wider than original at some point your narrowest settings will rub your fenders.

View attachment 152901

I was heading to my office to take this same picture from the manual.

 

[Jim Becker]

For the most part, the AI response is worthy of ignoring. It makes several unstated assumptions about where you are starting from. Then there is the point that a 72-inch setting isn't a thing. You can see in the manual page posted by MM-TX that the choices are in 4-inch steps starting at 66. A width of 72 is halfway between 2 choices. By "tire spread", I assume you mean the outside-to-outside width of your tires is 81 inches. Subtracting the width of one tire (about 11 inches) says your center-to-center is currently 70 inches. The only narrower option you have would be to change to 66 inches, the narrowest possible setting. I'm not sure there is clearance at the fenders for 66-inch tread with that size tire. You can check your current clearance. If not more than 2 inches, you can't go any narrower. (I know you can go narrower if you have 9.5-24 tires.) Your wheel center is already dished in. So any changes to the rim position will have no effect on the position of the wheel weights. If they are causing interference now, that problem will be unchanged.

 

[BarnyardEngineering]

The key to alleviating the confusion is, the loops on the rims ARE NOT CENTERED. They are 2" (give or take) off to one side of the center of the rim.

When you put them on the inside of the center/hub vs. the outside of the center/hub, that changes the width of the tractor by 2" per side, 4" total.

Swapping rims and tires from one side to the other gives you two more width choices because it changes where the loops are. You could achieve the same thing by turning the rims and tires around, but then the tires would be backwards and everyone would pick on you for that... "Hey, your tires are backwards." "Hey, why are your tires backwards?" "Your tires are backwards, STUPID!" Ugh...

 

[J.Wondergem]

That turning the tire thread backwards might work for him. Its a parade tractor, and if he isn't doing field work with it, supposably they will wear better. The concrete pullers all run theirs backwards.

 

[KJB34269]

As always, I appreciate your replies.