Front wheel drive switch

[lawdog1623]

Hey guys my truck didnt come with this front wheel drive switch feature. Can someone please explain it to me and also tell me if it is easy to equip a truck with this or not?

 

[73m819]

If you have a sprag, it does not have a air switch

 

[porkysplace]

You have a sprag transfer case . To equip with a air shift you have to change the transfer case and add air line and switch . Well worth the investment in my opinion.

 

[Tinwoodsman]

Where in Texas are you Lawdog?

 

[lawdog1623]

How large of an investment and how much work?

 

[lawdog1623]

Around sherman

 

[doghead]

Does your front drive function ?

I would leave it as is, if it does.

The difference is, with an air activated switch, you select front drive on demand.

The sprag, engages automatically when it senses wheel spin.

 

[lawdog1623]

Mine works i just figured if its moderately cheap i would update it

 

[SMOKEWAGON66]

So if a truck does NOT have the dash switch to engage the FWD, then it is a sprag transfer, and only engages FWD when the wheels spin? Ive often wondered this myself, as my truck does not have the switch, I always thought it was full-time 6X6. If this is not the case, maybe I should re-install my front driveline then eh?

 

[KsM715]

Yes put your driveline back. With no driveshaft, the t-case sees the front flange not spinning and the sprague will engage. Wether that causes any harm I do not know, however in either deuce (sprague, or airshift) without freewheeling hubs up front all of your front front driveline parts will be spinning reguardless. By removing the shaft,all you have done is removed a little weight, but everything else is still spinningin the axle and t-case

 

[73m819]

freewheeling hubs won't work on a deuce sprage set up

 

[SMOKEWAGON66]

....By removing the shaft,all you have done is removed a little weight, but everything else is still spinningin the axle and t-case

I know it will all still spin but w/o the d-line installed, wont that keep the front from being driven by the t-case and just become a free wheeling axle? The reason I took it out in the first place was to reduce wear and tear on the front as I never go offroad or need full time 6X6, plus it makes it a little easier to turn, since powered axles kick back slightly from the force on the U-joints and can wear tires in odd patterns. Ive been thinking that the permanent 6X6 might have something to do with so many deuce's cupping their front right tire...but who knows...just a thought.

 

[jbsapp]

Hmm, this is one of the things I need to get done this summer.

I verified that I have a Rockwell T 136 27 air shift transfer case but not the switch or any of the airlines and tees to connect it. I need to find an "airshift lockup kit".

 

[phil2968]

Cupping tires is usually the toe in settings are wrong. Found mine cupping bad and it was toed in bad.

 

[gimpyrobb]

The sprague only kicks in when the front moves 7% slower than the rears, so it is not full time 6x6. Also with the DS removed, the T-case will be engauged all the time, making un-needed wear on your sprague clutches. Sooner or later they will wear out and you'll lose 6x6 capability.

 

[doghead]

The sprague only kicks in when the front moves 7% slower than the rears, so it is not full time 6x6. Also with the DS removed, the T-case will be engaged all the time, making un-needed wear on your sprague clutches. Sooner or later they will wear out and you'll lose 6x6 capability.

TM 9-2320-209-34-2-1
9-4. AIR ACTUATED TRANSMISSION TRANSFER ASSEMBLY REPAIR. Refer to
TM 9-2520-246-34-1 for procedures to repair the air actuated transmission transfer
assembly.
9-5. DOUBLE SPRAG TRANSMISSION TRANSFER REMOVAL, REPAIR AND
REPLACEMENT.


We often misspell this(and that does not help when we use the search) so I am showing you an excerpt from the TM, to positively prove the correct spelling for SPRAG. (sounds like fag) Think you can remember it now?

 

[gimpyrobb]

While at work, I have no spell check. I am a crappy spellar!

 

[73m819]

Spell check always tells me that SPRAG is spelled WRONG, just proves what I already knew that spell check is not as smart as it thinks it is, if it was it would at least recognize some of the words that I type (sounds right to me)

 

[dmetalmiki]

73M819:freewheeling hubs won't work on a deuce sprage set up :

Can you quallify for the inexperienced transmission people on here WHY the free wheel hubs (expensive and recommended! ) modification in many previouse posts notes and encouragement don't work??. or by the same token therefore a waste of time and money.

An air shift negates the need. (freewheel hubs)Freewheels from the Hubs?

Sprag. Slipping conditions, not requiring 6x6 (freewheel hub) desired/selected by the driver). ((nothing rotates)).

Does Not engage as the driver Desired. Freewheels un-locked:
6x6 is selected by the driver (thro' sprag and freewheel hub).

 

[davidkroberts]

the sprag type transfer case is less desirable but Memphis Equipment has a kit to make them a bit better but Ive never used one personally. The 5 tons have a sprag that is much better than the one that comes on the M35A2 and nobody seems to have any problems with them. The lit may be something you could look into instead of going through the trouble of replacing a working transfer case.