REB Kit

[nf6x]

So one of the differences between the air operated sprang and the manual sprang is different gearing?

One of the differences between the sprag clutch transfer case and the air-shift transfer case is different front wheel gearing. The air shift transfer case doesn't have a sprag assembly.

There seems to be a lot of confusion around about how the sprag transfer works. It's sprag (referring to the type of clutch used in the case), not sprang, Sprague, etc.

The sprag clutch is an overrunning clutch. Think of the one-way action of a ratchet wrench, but with smooth operation instead of clicking. The front wheels are driven through one of these one-way clutches. The front drive is geared a little bit differently than the rear, so that most of the time that clutch is slipping and no power gets sent to the front.

When the rears start slipping but the front wheels still have traction, then the front wheels will be turning more slowly than the rears. Then the sprag clutch stops slipping, and starts sending power to the front wheels.

The different front wheel gearing is the key to making it work. If the front wheels were not geared differently, then the sprag wouldn't be slipping when the front and rear wheels were turning at the same speeds, so the front wheel drive would be engaged all the time. That would cause a lot more tire scrub and make the truck harder to steer.

That linkage between the transmission and transfer does not engage and disengage the front wheel drive. It changes the direction of the sprag clutch, much like turning the knob/lever on the back of a ratchet wrench.

The air shift case doesn't need to have different front wheel gearing, because it does not drive the front wheels through a sprag clutch. It just manually engages and disengages the front drive with a small air cylinder that's controlled by a valve on the dash.

I hope this makes things clearer.

What's wrong with the sprag transfer, anyway? The multifuel 5-ton trucks all have them, with no air-shift option.

 

[m139h2otruck]

Actually, if you want, the 5 tons can be "shifted" into neutral for the front drive by blocking air flow to the shifter and allowing the air cylinder to purge (zero pressure). The -10 manual describes how to do this for towing in reverse. We also tried this out by moving the truck in sand without the air fully up (not recommended).

 

[DDoyle]

[/quote]
What's wrong with the sprag transfer, anyway? The multifuel 5-ton trucks all have them, with no air-shift option.[/quote]

Amen brother!

 

[spicergear]

Hypothetically would it be possible to remove the over-running clutch (sprag) and use it in a different application? Very low power application? I have a need for a no-grab/spin-free for one direction and lock up/drive for the other direction. Hmmmm...

 

[paulopinto]

Any one knows where I can find the parts below to convert for manual front wheel drive ( transfer case t-136-21 ),
- 7521438-S Gear (22 teeth)
- 7372012-S Gear (33 teeth)
- 1363810 Gear
- 7372008 Spacer
and if all the parts for this purpose are these, and where it finds them, regards

 

[m-35tom]

all of these parts can be made, but in quantitys of 25 or more only. not that much money, but memphis may have rights to them.

 

[JasonS]

I doubt that Memphis has any 'rights' to them. Even if it was patented, I don't see any reason why you couldn't build your own. The gears are simple enough. I bought the last REB kit from Memphis. They told me that they did not have plans to produce any more due to increasing cost (and likely due to increasing availability of air shift transfer cases).

 

[paulopinto]

You are certain, in the Memphis do not have the 7372012-S(33 teeth) the other parts are OK. I´m thinking about disassembling and to confection new partGear 7372012-S, for this would like to have certainty of the relation of the gears and all the parts for the conversion .
It will be that it will give certain?
Thanks

 

[k5ontherocks]

*confused*.... what gear do you need for a reb kit? You can build one from parts found at Lowes or worthless depot!

how do you do this with lowes parts???

 

[ida34]

The biggest problem is finding the M35 aisle at Lowes. Once you do that it is a piece of cake.

 

[k5ontherocks]

The biggest problem is finding the M35 aisle at Lowes. Once you do that it is a piece of cake.

:lol

seriously though......?

 

[k5ontherocks]

*confused*.... what gear do you need for a reb kit? You can build one from parts found at Lowes or worthless depot!

how do you do this with lowes parts???

anyone out there know this answer??

 

[rizzo]

anyone have a picture of the sprags clutches?

 

[gringeltaube]

anyone have a picture of the sprags clutches?

Maybe this helps...?