Hey guys.
So since I bought my truck 4 years ago, its always been a hassle to get it into 4wd.
Ive changed the fluid twice in that time which makes it easier for a few lock ins (literally, few), but then goes back to being a pain.
Ive also replaced 2 of the vac lines when they kept sliding off there connections.

Now that Im going to the drag strip during the summers Im gettin fed up with it.
Im tired of having to start tryin to get it into 4 wheel when im still 5 vehicles back and barely gettin it locked in as im next in line!

Anyone have any ideas why I cant get it locked in sooner?

Any ideas would be great.
TIA Ian.

 

Bump anyone?

 

Looks into the POSI lock system that manually engages the actuator instead of the vacumm design.

 

Are you talking about this..

http://www.puredieselpower.com/catal...t-p-25235.html

Ive been seriously thinking about this kit, but wondering if a 20-50$ fix would make my 4wd work well befor spending 200 on it ya know.

Also, I have no idea if I have CAD.

"Works on 1994-2002 Dodge 2500/3500 trucks with CAD (Central Axle Disconnect)" - From Pure Diesel Power site

 

Check your linkage. Mine was a bear to get in after I had my trans rebuilt. I loosened the main rod and gave it a little slack and now it goes in like it used to.

 

If I remember correctly, the fork in the CAD can get bent and at times be hard to engage..

 

Is it hard to move the t-case lever into 4wd, or does it take too long after shifting for the light to come on? If it's hard to shift, need to take a close look at the linkage (as described above) or if that checks out, look inside the transfer case for worn synchros or anything broken, or a bent shift fork/missing contact pads. Or if you don't want to take it all apart it should go in just fine with the truck off in neutral. If then it still is hard to shift the t-case has to come apart to see what's up.

If it's slow to engage after shifting, check the CAD (pass side axle, can't miss it if you have it) to make sure it holds vacuum. Best to take it off the axle to check, with the passenger side wheel up in the air a few inches so no fluid leaks out. The shift collar should move back and forth freely once the 2 shafts are lined up, and the shift fork should sit in the collar nice and straight, look for any uneven wear marks if it's bent. Good luck.

 

No its not hard to shift the stick, it shifts real easy.
Just takes forever for it to get locked in AND the light to come on. the light is accurate as far as when its in and when its not. Just take forever to get locked in!!

Ill have to take a look in the day light and see if I have CAD and go from there I guess. Thanks guys. Keep any info rolling if ya got it.
Thanks

 

Alright so I looked at it today and as far as I can tell, its just the vacuum bolted up on the passenger side of front axle.
Is that reffered to as the CAD? the Vacuum?

If I dont have CAD then is it just solid axle fron the fron dif over to the end?

This might be a stupid question but.. Is CAD a 4x4 thing only, or do 2 wheel drives have it too?

 

Yes that is the CAD (center axle disconnect) unit, and yes it is only for 4wd trucks. All it does is break the shaft going from the differential to the passenger wheel, so when in 2wd you are not forcing the differential to "differentiate". This is all instead of the mechanical locking hub setup, same idea though. It should actually have 2 vacuum lines, one pulls in the collar to connect the two shafts for 4wd, the other pushes it away to break the shaft into 2 separate pieces.

If you pull the 4 bolts around the vacuum actuator it all makes sense pretty easy. Hook a vacuum line to each port on the actuator to make sure it works in both directions, from a hand pump (mighty vac) or even a test line from the truck or another car.

While you're under there might want to make sure you're getting vacuum to either line, I forget which is which, but a mighty vac has a gauge on it. If you plug the hand pump into one line, then the other line it should show vacuum switching from one line to the other when shifting.

 

Alright its making sense. Ill hopefully be taking it off tomorrow and taking a look inside and what not. I think I mught end up getting the kit I posted the link to earlier just for ease. But atleast for now I can see whats up and if I can do anything to hold myself over.

Thanks gorms and guys!

 

2 words to fix that problem for good ---- Posi - Loc

 

Search on Posi-Lok - you will find a few responses from me about it. On the advice of guys on this forum I ditched the vacuum activated CAD last fall and went with a Posi-Lok. Great product, well built, no leaks, works every time and installs in a couple of hours. Once you are done, you will wonder why you waited so long to do it. If you want more info, let me know. Cost me $200 in Calgary, AB.

 

You may want to check your vac lines thru-out the truck and make sure you're all connected and plugged. May save you some money.

I thought you were having trouble shifting, not engaging.

 

um..pull the lever..assuming that you are in neutral, its PIA other wise.
then rock the steering back and forth..moving forward/backwards also helps.

I have a true track(rear end) on my 1500..manual. many time when I pull the level the CAD doesn't engage..move, rock the steering..then it lock in 4x4..

I'm wishing my 2500 had the same rear end..at the moment its open..why Dodge made a 4x4 with open diffs is beyond me..

-dkenny