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4 wheel drive problems

1013 Views 8 Replies 4 Participants Last post by  lukee1982
1999 dodge ram qc 4x4 5.9 231d is what is said on the t-case.
well I have a problem with something in my 4-wheel drive.

while driving down the road in 4 hi it off and on will kick out of 4h making a loud "clunk" from what seems to be the passenger front.

-have changed t-case fluid- was dirty
-checked diffferential fluid level -was a little low
after changing the following it has taken longer for it to make the "clunk" however it still does it especially when accelerating from a dead stop in 4hi

also it has been taking longer to engage and disengage 4h or 4lo

thanks for all your help
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Thats freaken crazy, mines doing the exact same thing. please let me know if you find out any thing and i'll do the same. I did pull it apart though and i found a piece of a shift fork pad laying in there. Could it also be that the chain is loose and its slaping against the side of the chase? guys please help us, winters coming and 4H is a must ( not trying to hijack your post. im just getting desprite too. )
Might be issues with your CAD unit not fully engaging if you think the noise is coming from the passenger front. Could have a bad bushing of something. Might not be transfer case related at all. Check around here for a post on the CAD unit bushing going bad. There was one on here about a week or two ago.
CAD is Central Axle Disconnect. It is the vacuum actuated part on the rear of the passenger side front axle tube. If it is slow to come in and out of 4wd, I'd guess your CAD unit is acting up. That is what actually engages the 4wd in these trucks. It is kinda like locking in the hubs on other 4wds.
i wonder if that could be it because my truck was hit. could that cause it? is there any way to check besides taking the front driveshaft off and seeing if it still does it?
insted of taking of the drive shaft i could just disconect the cad system right. then if i doesnt do it i know its the cad. anyone know how i should go abour disconnecting it???
Usually what gets messed up is the air lines to the vacuum housing.

Pull the right air line off the vacuum housing. If you hear a decompression sound and a clunk, then your lines are clogged. The less sound and noise, the less clogged your lines are.

For instance, my air lines are completley clogged from when I broke one and sucked in mud and water. Everytime I want 4wd, I need to shift the transfer case, get out of the truck, and pull off the right vacuum line. When I do that there's a WOOSHH and then a CLUNK as the shift fork engages. I pop the air line back on and hit the trails.

Soo, try pulling off the right air line and then re-connecting it. If the problem is gone, then you have clogged air lines. If not, then the vacuum itself could be damaged
so chris, your saying I should pull the right hose of the axle and it should ingage into 4H or it will disengage. im confussed. maybe i'll just call you tomorrow when i do it and you can walk me though it.
I only have vacuum on the red I believe right side vacuum line is this correct?
or should there be vacuum on both sides?

thank you
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