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Transfer case shifting ....

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'02 RC 5sp. ....2500 4x4

The transfer case will shift from 2HI to 4HI easily when stopped.  Moving, it's difficult. Grinds.

Shifting out of 4HI to 2HI on the move is very easy.

Any ideas ?

Also, could not find out what 'CAD' means in the acronym list. Does this term apply to my situation.

Thank you,


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Cad is the vacuum actuated collar on the front axle that locks the inner shaft to the other.  This is needed to engage 4wd.


How are your fluid levels?  


There is a syncing ring in the transfer case.  Tear down is easy and we have an article for it.


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CAD stand for central axle disconnect and is the large vacuum operated collar found on the 2nd gen Dodge 4wd truck front axles, but were faded out in '02.  Although because the assembly lines equipped what they had before re-tooling, there's plenty '02's with them.  So you need to know what you have and its easy to recognize too as if you have the CAD truck then there would be a large collar looking thing on the passenger side axle tube of the front axle.  If you dont then the axle tube will look normal.


If you have the CAD then the 4wd system is part time which means the front driveshaft isnt turning at road speeds while you drive.  So in order to shift into 4wd there's a syncro ring in the transfer case which speeds up the driveshaft when engaging 4wd.  You're not supposed to engage at speeds over 10 mph but really its best to be barely rolling forward when shifting the TC.  If the speeds are too fast then the syncro gear has to speed up a heavy shaft which wears it out.


If you dont have the CAD and its grinding then thats not normal as the non-CAD trucks are full time 4wd systems and the front driveshaft is always spinning road speed and engaging 4wd is as quick as pulling the lever back to 4 hi.  Of course you NEVER want to shift into 4 lo unless you're pretty much fully stopped. :thumbup2:

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Mine is a CAD equipped vehicle .....

As you mention, it's best to shift below 10mph ..... I did not know this, and the Owners Manual procedure is quite vague.

I will re-check the fluid level, and adjust my driving habits.


I've been trying to shift it like the NP205 equipped '91.5 5sp ........ easy at many speeds.

Appreciate the good information ......


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