I bought a 95 ram 1500 5.9L from a so called "mechanic" over a month ago. Well, I've put a new tranny and a lot of other stuff into it trying to get it road ready. Finally got it on the road the other day and noticed that even though I had it in 2wd it drove like a truck that was in 4wd......it was.

Well, the indicator lamp switch is broken and the actuator is "stuck" in 4wd.

I'm no expert on these CAD axles, but i think that this guy has improperly assembled the 4wd actuator unit. The fork was not between the two c-clips, but rather on the outside of the last one. So, the way I see it, no matter which way the actuator went, the fork couldn't move. So, does anyone have a pic of how this SHOULD go back together?

Also, I took the actuator free of the rest of the assembly, and hooked it back up to the vacuum lines. When I shift to 4wd, it pushed straight out, but when I go back to 2wd, nothing. I can press it back in by hand and it will stay until I shift to 4wd again. So, is this unit pretty much busted? or am I missing some sort of spring in this assembly?

I'm kinda clueless on this right now.

 

this shows how it works.
http://dodgeram.org/tech/repair/4X4/4x4_engagment.htm

when you remove the cad, it will have a fork attached. the fork should be in grooves of the collar. the collar must EASILY slide back and forth over the 2 axles halves. if it doesn't move easily back and forth, you'll need to fix it by replacing the 2 bushings, or the collar, or filing burrs off the splines. mine had burrs which made it a very tight slide.

edit - fork should lay inside the outside rims of the collar, so it can move it back and forth. so its very important to line it up right when installing.

the vac lines from the t-case should switch from one (2wd) to the other (4wd) based on t-case shift position. verify that you always have vac on one or the other. no vac on either is bad.

when vac is applied to one port of the cad, the fork should move to one side. when vac is applied to the other, it should move back. if not, it needs repair or replacement. its pretty simple, generally a sticky shaft.

edit - after install. put the truck up on 4 jack stands to crank it and operate things. verify front drive shaft is turning and both front wheels are spinning. shut off truck while in 4wd. spin passenger side forward by hand. drivers side should spin backwards. crank truck and shift to 2wd. repeat test and verify passenger side spins freely, unlocked from drivers side.

congrats, you'll be an expert soon by owning a dodge.


after you've fixed it a couple of times and you get tired of working on it, replace it with a manual posi-lok cable for about 200. this also provides 2wd low, which is nice.

 

seems simple enough, but i did notice that one of the bushings that you referred to has a chip out of it. I have tried, but cannot seem to find any parts to replace it with. Has anyone else found these for sale? or better yet, what is the actual name for them?

 

i bought one or both from the link below. for the larger bushing in the inner side housing, i replaced the bushing with the older year's bearing. they are interchangable and that remove some play. for the smaller bushing between the 2 shafts, i replaced it to remove even more play. replacing these bushing requires removal of passenger side shafts, seal, bearing, etc. i dreaded this for a long time but finally broke down and did seals on both sides and did the bushings while i was in there. i expected my hard axle couple to be all bushing problems, but was surprised to find that most of the problem was burrs/tight fit on the axle splines at the collar.

here you go.
https://dodgeforum.com/forum/2nd-gen...-bearings.html

 

I have a 2001 Dodge Ram 1500 5.2 5 speed 4wd. I've checked vacuum at all spots that there supposed to be checked at. I have the right amount of vacuum. I recently replaced the passenger side inner axle seal and my 4wd worked after that. Then I hit 4 deer and ran over 3 of them and now my now my 4wd is not working. When it wasn't emgaging in 4wd I pulled the cad unit and made surey clips were in tact, afterwards my 4wd light stays on And dosent engage. When I pulled the cad unit off and hooked air pressure to it, the form slid over and back so I reinstalled. Now my 4wd light is stuck on but I don't have 4wd. Any help

 

Sounds like the CAD is working to lock the front axle but the transfer case isn't engaging 4WD to turn the front driveshaft. Check the transfer case linkage and the vacuum lines going to the transfer case to ensure they are intact. The last time I had 4WD issues, I jacked the truck up onto 4 jackstands (one on each corner) to allow me to run the truck in 4WD and get up under the truck to see what's going on better. I ended up fixing a transfer case/shifter linkage issue that kept my truck from going into 4WD.

 

I have already done that and almost anything you can think of. I've already ordered the posi-lok Install kit but I'm not sure if I really want to install it if I can fix the real problem.

 

How did this happen and what else got damaged? You may have vacuum at the cad but not enough. The metal lines along the frame rust and can get blocked if moisture gets in. Do you vents work? If not the check valves aren't allowing vacuum to accumulate in the reservoir witch effects the cad operation also. When you had the cad off did you look at the slide collar and the gear? They can get chewed up.

 

What does everyone recommend for a replacement if the diaphragm is bad?

Obviously the Dormans are ubiquitous but I'm loathe to buy anything Dorman. I'd only do it thru AutoZone or O'Reilly for the LT warranty but swapping a failed Dorman once a season (I'm only guessing, based upon every other piece of garbage they produce) seems like an unnecessary hassle...

 

I put the dorman actuator in my 96 truck, and drove it for several years without issue. It was still working when I sold it. For the most part, I try and avoid dorman, but, it isn't always practical.