Why won't my sprag engage?

[two.fiveM35]

Swapping a sprag for air shift?

Finally had the chance to see if my sprag transfer would engage. And it did not. Figured out I have an air shift transfer case and no air shift switch. I think when they rebuild the truck they just threw in a transfer case that they had in inventory.

Has anyone switched from a sprag to air shift? How much work is it to get all the air lines and associated stuff installed to get this thing to work?

 

[Field Artillery]

I have the same problem. Would love an answer from one of our wizards.

 

[wsucougarx]

You can buy the airshift switch kit on ebay for like $40 or so. I checked ebay and didn't see anything offered. They are typically described as Airshift rebuild kits or Airshift upgrade kits.

 

[3rdmdqm]

Interesting question on the sprague. Mine does not have an airshift however it would not engage either. I checked the TM's and did the adjustments and it seemed to be adjusted properly. However when backing if not perfectly straight, when placed into forward drive the stearing wheel would start to violently shake and then there would be a loud bang like something in the transfer case exploded. I have removed the front wheel drive shaft until I figure out what is going on. I'm thinking its some type of adjustment issue where one of the rods is not engaging or disengaging completely during shifting from reverse to forward but haven't dug into it yet. I did notice that taking off the front drive shaft got me about 5 more mph on the hwy and no more problems.

 

[Field Artillery]

What would be involved if I have a sprag and want to change to the airshift? New transfer case or more parts? Can it be done?
Thanks

 

[jasonjc]

Yes new case and some parts or no case and alot of parts. The air shift case has different grears in it. Get a air shift case and a air kit. It should take a good mech a day to do it all maybe a weekend. I have a NOS air kit I can take pic of and get the parts list from if anyone needs it. No not for sale as I need 2 for myself and only have 1.

 

[2027Deuce]

3drmdqm you deffinately have something wrong in your sprag, remember to also go from reverse to 1st even if rolling downhill, this puts the transfer in forward. It maybe the link between tranny and transfer, TM specs the exact length it needs to be. Also run with your front axle back in at times, all the bearings and goodies in the front axle get oil this way.

Switching to an air shift can be done, do a search cause others on here have done it.

 

[two.fiveM35]

jasonjc i would like to see the parts invovled it hookinking air to it. Thanks

 

[hole]

Hope this helps http://www.steelsoldiers.com/deuce/17892-air-shift-install-parts-t-case-install.html

 

[stumps]

Interesting question on the sprague. Mine does not have an airshift however it would not engage either. I checked the TM's and did the adjustments and it seemed to be adjusted properly. However when backing if not perfectly straight, when placed into forward drive the stearing wheel would start to violently shake and then there would be a loud bang like something in the transfer case exploded. I have removed the front wheel drive shaft until I figure out what is going on. I'm thinking its some type of adjustment issue where one of the rods is not engaging or disengaging completely during shifting from reverse to forward but haven't dug into it yet. I did notice that taking off the front drive shaft got me about 5 more mph on the hwy and no more problems.

If I am understanding you correctly, you had your transmission in a forward gear, and you allowed your truck to roll backward. Is that correct?

Or do you mean the problem happens when shifting from reverse to forward?

If you allowed your truck to roll backwards when it was in a forward gear, you violated the only rule that must be obeyed with sprag transfer cases. Do not ever for any reason let the truck move in other than the direction of the shift lever.

-Chuck

 

[WillWagner]

Sprags are a PITA. Alot of people say they are just as good as the air shift. I have had both, the air shift is hands down way better. You know when it is engaged...when you flip the lever. I adjusted my sprag by the TM, with David Doyles help, with a retired Army mechanic and it still didn't work when it was needed. The front tires also wear faster with a sprag. I wasn't rushing and had the sprag out and the air shift in minus the plumbing in less than a full day, IIRC about 6 hrs. Took another 2 hrs to plumb the air. My , if you are inclined and have the time and $ to spend, do the swap. If you use the truck off road, it will be worth it.

 

[appnut1]

Go to an air shift I had a sprag would adjust it and the next time you went to engage it was not there again. Ver frustrating

 

[JasonS]

People assume that the sprag needs to be adjusted if not working. IMHO, it is usually because the sprag elements are worn out. The adjustment is not that sensitive.

 

[RollingThunder19]

I'm having issues with my sprag I noticed in 1st and reverse itll only engage sometimes. When it does it's great gets me right out of the situation other than that rear tires just spin and nothing from front axle.

 

[RollingThunder19]

Also I see that some talk about adjusting the linkage for the sprag? What's the best way to try and do it and how detailed is it?

 

[doghead]

Please do not cross-post(post the same thing in more than one thread or forum).

 

[tobyS]

Are you sure you have an air shift TC or could that be the sprag cylinder that moves it from forward to reverse? I don't know about the deuce, although I expect it is near the same as the 809 series....the gearing inside the TC has different ratio of the front and back so the back is always trying to over-run the front (in forward). Bang could be relief of the difference when the sprag is not in the correct position for the direction of travel.

The "switch" for air shift is nothing but a 2 position 3 way manual air valve....many suppliers.

 

[Ajax MD]

It's great to learn that it's easy to convert to a switch style activation.

 

[tobyS]

It's great to learn that it's easy to convert to a switch style activation.

I hope you are not talking about a manual switch for changing the sprag. Mine, I believe was hooked to the backup switch.

Some people claim there is a neutral in the sprag's positioning, but I didn't see that when I had mine apart.