4wd, front axle not engaging.

[Megadan]

I've been stewing on this one for a while trying to figure it out, but short of going and getting another transfer case from the yard, of which there are 2 good ones I can pull for 90 bucks.

When I had all 4 wheels off the ground last weekend I decided to test and see if my 4wd actually worked, because this winter it never felt right.  Sure enough, the front axle and driveshaft just sit there doing nothing.  I even risked my hand and turned the front shaft by hand and it just spins freely while the rear wheels turn away.  

Before you say to adjust the linkage, which seems to be everybodies go-to reponse, the truck engages 4hi and 4lo perfectly, just in 2wd mode.  Thought it was the CAD, but my cable is engaging the outer passenger axle stub.

Only thing I can figure is something internal let go. Doesn't make a single noise.  Checked the fluid for metal, found nothing. Checked inside the case as best I could. Chain is not visually slack, and when I prod it with my finger through the fill hole it feels pretty tight.  The only thing I can figure is some sort of shift fork, or pin, broke in such a way that it didn't cause any catastrophic failure, but won't let me engage the front driveshaft.

Another T-case is cheap and easy enough to get, and I may go that route anyway.  Then I can build myself a heavy duty case with the current one with a wide chain and 6 pinion setup.  Just seeing if anybody has any other ideas or things to check for.

[87MJTIM]

I assume you have the CAD.  Is there a vacuum leak any where in the lines?

 

Perform the CAD elimination and move on.

[Megadan]

I assume you have the CAD.  Is there a vacuum leak any where in the lines?

 

Perform the CAD elimination and move on.

If you notice I mentioned CAD and my Cable (aka Posi-Lok).  cable means I already removed CAD.    :doh:

 

Also, you may have noticed I said the front driveshaft freewheels when 4wd engaged, and that I can grab and turn said shaft by hand while in 4wd and the rear driveshaft chugging away.

 

Not trying to be a jerk here, but I included all of the information in my first post that should be relevant.

[rearview]

Did you check the adjustment on the flux capacitor?

 

You can pick one up at the parts store pretty cheap.

 

http://www.oreillyauto.com/site/c/detail/EB00/121G.oap

[Megadan]

Already have one of those with a Mr. Fusion.  didn't make a difference.  :hmm:

Oddly enough though, I keep ending up really late or really early everywhere I go...

[Rockfrog]

I would suspect the tabs on the shift fork snapped off or the fork is bent  ... so the fork moves but doesn't really do anything.

[Jtrux]

They are easy to split apart. You can even do it with the case mated to the tranny under the truck relatively easily. Split it apart and take a look.

[Megadan]

Eh, I have RWD, and any sort of repair like that will require putting my truck down.  I think I will just go snag another T-case, clean it up, inspect it, put new seals on it and swap it around.  Will give me a good followup when I take apart the one currently installed.

[ComancheKid45]

Yep, get another, split it open and slap a new chain, fork pads and seals in there and you'll be good to go.