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Discussion Starter · #1 ·
Okay i have a 88 4x4 It has the auto hubs on it. My hubs wont lock. Every thing under the truck locks and goes into 4x except the hubs wont spin. If i convert the truck to manual hubs will my 4x4 come back? I can get a set of warn hubs and the conversion kit form advance for pretty cheap. Is this a waste of money or will it work and get my trucks balls back offroad? ??? Please say it will work. Please say it will.
 

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u dont have auto hubs, u have full time hubs, unless someone swapped in auto hubs. if ur not going into 4x4, i would check the CAD and Tcase.

Duane
 

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CLRracer said:
u dont have auto hubs, u have full time hubs, unless someone swapped in auto hubs. if ur not going into 4x4, i would check the CAD and Tcase.

Duane
Exactly.
I'm thinking that myself, or somebody else should write up an explanation for the FAQ section, that explains how CAD works. There always seems to be some confusion about CAD vs. auto hubs.
 

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Discussion Starter · #5 ·
the t-case works fine. The axle works fine. But sadly the cad is junk. Every thing locks up when in 4x but the auto hubs wont lock. The axle goes into 4x and everything but the front wheels dont spin. It woudl make since that since everything else is workin and i converted it over to manual locking hubs than my 4x would work again. I really dont understand why it wouldnt.
 

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Like Duane said, unless somebody converted it (which would be a stupid thing to do) you DO NOT have auto hubs. It's more than likely your CAD is the problem and putting manual hubs on alone, will not fix it. You would also have to lock your CAD.
This is an explanation I typed a couple of weeks ago for somebody else and I finally got smart enough to copy it so I don't have to keep typing it. It was directed at somebody else's questions, but most of it will benifit you:

One good way to test if your CAD is locked when it shouldn't be is to: park it in 2wd, with engine running, crawl under and see if you can turn your front drive shaft with your hand. If you can, its not locking prematuely (at least not at that instant ::)). If you can't turn it, that means its engaged or partially engaged.
As far as your last question, lets back up a little bit and explain what CAD does:
CAD (central axle disconnect) is Dodges method of "shift-on-the-fly" 4wd engagement. On the long side of your front axle, there is actually a two-piece axle inside. Where you see the "bulge" with a vacuum motor on top, that is where the two-piece shaft engages/disengages (with a sliding collar) when it gets a vacuum signal from the t-case when you shift in/out of 4wd.
Your hubs are basically "full time" hubs, they are always engaged with the axle. When you are in 2wd, the axle is spinning, but it is disengaged (because the collar is not connecting the two shafts) from the inner shaft that goes into the diff.
On the passenger side, the axle shaft is one piece and does go into the diff, but it is only spinning the spider gear in there and the carrier/ring gear is not turning.

There are a couple of reasons to put manual hubs on. If your CAD is giving you trouble, you can lock it (see the FAQ on this process) and of course you need the manual hubs on so you're not turning your whole front drive train. This of course means you don't have true "shift-on-the-fly" anymore.
I put manual hubs on mine so I could have 2-low. I still have my CAD functioning normally and it has always been flawless for me. The reason that I stick with CAD is that I need 4wd daily to get to and from my house and it would get really annoying to have to get out and lock/unlock hubs all of the time. So, I can just leave my hubs locked in all of the time, and this is no different that the fulltime hubs that it came with, but now, I can get 2 low if I want, and I can just unlock them and save wear and tear (which is minimal) on the shafts, u-joints and spider gears.
 

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Discussion Starter · #7 ·
that is disappointing. blast it. Well m-f. I was tryin to get out of messin with that stupid cad box. I just want the 4x back thats all i want.
 

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Discussion Starter · #8 ·
when i put it in 4x and crawl up under the truck and try and turn the d-shaft it wont turn.. What does that mean? that the cad is locked? so why wont my front wheels get any power?
 
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Here are some pics that might help you understand what the cad is





The right wheel is connected to the axle directly in a similar fashion to a full-time 4wd axle. The left axleshaft consists of two shafts: one engaged to the differential, the other to the left wheel. A sliding sleeve connects the two separate shafts when 4wd is engaged. While in 2wd, the left wheel turns the spider gears and through it, the right inner axleshaft. Since the two left shafts aren't connected, the left wheel is free to turn independently of the right. While the spider gears spin, the ring gear, and thereby the front driveshaft, stay stationary -- allowing for a decreased amount of drag on the driveline.

When you engage 4wd, a synchronizer in the transfercase spins up the front driveshaft; at the same time, a vacuum switch opens, causing the vacuum motor in the CAD to try and lock together the left axle shafts. Engagement does not occur until the splines on the shaft lines up with the ones on the sleeve. As the sleeve slides over, it trips an electronic switch, turning on the 4wd light in your dash.
 

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I'll second that opinion of posting this in the FAQ's. I just asked about the CAD a couple weeks ago. And thanks for the info guys. Since I'm in a hurry to get mine fixed I figured I'd just take it to the local Dodge dealer and have it done. Well after a 10 minute argument with the head mechanic, I left the place 30 dollars poorer, and still had a front driveshaft that was turning all the time. I guess even Dodge mechanics have no clue how the CAD system is supposed to work!

Roy
 

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Put the truck up on 4 jackstands, put it in 4wd, a then in gear. If it's truly in 4wd, obviously, the front wheels will turn. If not.....then check that the shift fork in the CAD housing is pulling the collar towards the D-side tire when in 4wd. It could be simple, like a disconnected vac hose. If the other stuff checks out, what if you've broken an axleshaft out mud-whumpin'?
 

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I'd try that
 

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Now if someone wants to write up something for the FAQ section and put the pics from above in there, you're more than welcome to :)
 
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To lock your cad remove the cad unit.
take all of the little e-clips off of the shaft that the shift fork is on
slide the fork over to the red area on the shaft and put the
e-clip on so the yoke stays put.



to reassemble
move the collar inside the axle so that the fork lines up on the collar and bolt the unit back onto the axle housing.

The cad is now locked now you can put the lock out hubs on.
 

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Discussion Starter · #18 ·
thanks alot! Now that is what i have been wanting for months.....some pics of how to do this.!!!! THANKS ALOT! It doesnt seem that hard now. Me and my dad will try and do it this weekend.
 

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Discussion Starter · #20 ·
the cad was unhooked on my truck when i got it. But the 4x worked. Some one locked the cad before. THe vac hoses are all there fromm what i can see.
 
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