The Ford Barn

NCSUDucker · 06-21-2025, 08:56 PM

Looking for the correct wheel cylinders for a 39 1 ton truck. Got a little confused looking at the green bible/searching online. I think I have found the front at CW Moss.

https://cwmoss.com/collections/brake...-right-1939-48

https://cwmoss.com/collections/brake...mbly-1-x-1-3-8

But I'm struggling with finding the correct rear cylinders as most say "except 122" wheelbase"

I can find the rear for a 3/4 ton 122" wheelbase and a 1 ton but it says "except 122".

Truck is at the mechanics right now so a visual reference isn't possible for me, brakes were fading bad last time I drove it. Assuming it is the master cylinder which I already have but wanted to have the parts on hand in case its one or more of the wheel cylinders causing the problem.

Thanks in advance.
Brad

cas3 · 06-21-2025, 11:29 PM

If the brakes were "sorta" functioning, maybe the cylinders can just be rebuilt.

Often, there is a wagner part # on the cylinder

GB SISSON · 06-22-2025, 07:58 AM

My experience on the early 122" tonners was that The front brakes were based on the 1/2 ton parts and the rears on the 1 1/2 ton parts. Drums being the exception. Chuck at 'Chuck's Trucks' in Conneticut could confirm this. I can attest to seeing 'except 122"' over and over again in the green bible.

GB SISSON · 06-22-2025, 08:09 AM

Quote:

Originally Posted by cas3

If the brakes were "sorta" functioning, maybe the cylinders can just be rebuilt.

Often, there is a wagner part # on the cylinder

I have a friend who's very deep into GM big trucks. He has a bunch of them. First thing he does is pull all the wheel cyls and the master and sends them to his favorite machine shop for stainless steel sleeves. Because of this he has never gotten one back that didn't fit his application, and they last a lifetime with no rust pits.

Bob C · 06-22-2025, 10:48 AM

The green book shows 92Y-2261 122" 1 ton truck rear 1939-47.

NCSUDucker · 06-22-2025, 08:57 PM

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Quote:

Originally Posted by Bob C

The green book shows 92Y-2261 122" 1 ton truck rear 1939-47.

Quote:

Originally Posted by GB SISSON

My experience on the early 122" tonners was that The front brakes were based on the 1/2 ton parts and the rears on the 1 1/2 ton parts. Drums being the exception. Chuck at 'Chuck's Trucks' in Conneticut could confirm this. I can attest to seeing 'except 122"' over and over again in the green bible.

Thanks GB, that was my understanding as well.

NCSUDucker · 06-22-2025, 08:59 PM

Quote:

Originally Posted by Bob C

The green book shows 92Y-2261 122" 1 ton truck rear 1939-47.

I know but when I look that part up for sale it's showing not for 122" wheelbase
https://cwmoss.com/products/wheel-cy...33099398938667

That's where the confusion for me is coming in

NCSUDucker · 06-22-2025, 09:28 PM

Quote:

Originally Posted by cas3

If the brakes were "sorta" functioning, maybe the cylinders can just be rebuilt.

Often, there is a wagner part # on the cylinder

That's where I'm leaning, I'm honestly just hoping it's the master cylinder but would like to have the parts on hand just in case.

Bob C · 06-22-2025, 10:20 PM

I think the CW Moss listing is wrong. I looked up 92Y-2261
on a couple of other sites and they show 1 3/8" Bore and Moss shows 1"x1 1/8".

cas3 · 06-23-2025, 12:26 AM

Since it has to come off anyway, take it off, take apart, the cup size is usually on the rubber cups. If its been moving, its a good chance a hone job and new rubber cups will fix that part. Do the master cyl first, Then with the right rear line disconnected, pump the brake pedal slowly until you get clean fluid. No need to close the bleeders, it will work doing it slow. ( hose connected-dump in a clear jar).

Then, connect the rear lines, and do the same at the front right. Theory is aways start at the cyl furthest from the master.

After you get al the brown icky fluid out, bleed as normal.

Napa I believe still sells the cups only, not a cylinder kit, I always just clean up the pistons and spring.

06-21-2025, 08:56 PM	#1
NCSUDucker Member Join Date: Jun 2024 Location: Salisbury, NC Posts: 67	Brake Wheel Cylinder Help Looking for the correct wheel cylinders for a 39 1 ton truck. Got a little confused looking at the green bible/searching online. I think I have found the front at CW Moss. https://cwmoss.com/collections/brake...-right-1939-48 https://cwmoss.com/collections/brake...mbly-1-x-1-3-8 But I'm struggling with finding the correct rear cylinders as most say "except 122" wheelbase" I can find the rear for a 3/4 ton 122" wheelbase and a 1 ton but it says "except 122". Truck is at the mechanics right now so a visual reference isn't possible for me, brakes were fading bad last time I drove it. Assuming it is the master cylinder which I already have but wanted to have the parts on hand in case its one or more of the wheel cylinders causing the problem. Thanks in advance. Brad

06-21-2025, 11:29 PM	#2
cas3 Senior Member Join Date: Jan 2011 Location: Beverly Kansas Posts: 5,297	Re: Brake Wheel Cylinder Help If the brakes were "sorta" functioning, maybe the cylinders can just be rebuilt. Often, there is a wagner part # on the cylinder

06-22-2025, 07:58 AM	#3
GB SISSON Senior Member Join Date: Jan 2014 Location: Orcas Island Washington Posts: 5,881	Re: Brake Wheel Cylinder Help My experience on the early 122" tonners was that The front brakes were based on the 1/2 ton parts and the rears on the 1 1/2 ton parts. Drums being the exception. Chuck at 'Chuck's Trucks' in Conneticut could confirm this. I can attest to seeing 'except 122"' over and over again in the green bible. __________________ Owner/Operator of 'Jailbar Ranch' on the side of Mt. Pickett. Current stable consists of 1946 1/2 ton pickup turned woodie wagon with FH V8, 1946 Tonner Pickup with 226 H six, 1979 Toyota landcruiser wagon, now wearing 1947 Ford Jailbar sheet metal. 'Rusty ol' floorboards, hot on their feet' (Alan Jackson)

06-22-2025, 10:48 AM	#5
Bob C Senior Member Join Date: May 2010 Location: So Cal Posts: 9,359	Re: Brake Wheel Cylinder Help The green book shows 92Y-2261 122" 1 ton truck rear 1939-47.

06-22-2025, 10:20 PM	#9
Bob C Senior Member Join Date: May 2010 Location: So Cal Posts: 9,359	Re: Brake Wheel Cylinder Help I think the CW Moss listing is wrong. I looked up 92Y-2261 on a couple of other sites and they show 1 3/8" Bore and Moss shows 1"x1 1/8".

06-23-2025, 12:26 AM	#10
cas3 Senior Member Join Date: Jan 2011 Location: Beverly Kansas Posts: 5,297	Re: Brake Wheel Cylinder Help Since it has to come off anyway, take it off, take apart, the cup size is usually on the rubber cups. If its been moving, its a good chance a hone job and new rubber cups will fix that part. Do the master cyl first, Then with the right rear line disconnected, pump the brake pedal slowly until you get clean fluid. No need to close the bleeders, it will work doing it slow. ( hose connected-dump in a clear jar). Then, connect the rear lines, and do the same at the front right. Theory is aways start at the cyl furthest from the master. After you get al the brown icky fluid out, bleed as normal. Napa I believe still sells the cups only, not a cylinder kit, I always just clean up the pistons and spring.