I have a 1995 dodge 2500 5 speed. I bought it a few months ago, and made the mistake buying it when it was 10 degrees outside. I thought it was a good running truck, well it was until it started warming up it. Long story short, I had to replace the injection pump on it. Hurt my wallet, but I learned a lot by doing it myself. Now I have noticed my 4x4 isn't working. The owner before me installed a posi-lock on it to replace the vacuum actuator. It will shift into 4x4 but I have no power at the front tires. I jacked up the truck and put it into 4x4 and the front tires will spin but i can stop them with my hands. I feel a slight tug when I have them stopped. I would like to get it fixed. I work on farms and it sucks when I have to get the tractor to pull me out of the field every time it rains. Has anyone else had this problem with their 4x4? What do I have to do to fix it?

 

I can't tell what problem you're having exactly, but I would start with the CAD unit. So, the PO installed a posi-lock to replace the vacuum unit, probably because something wasn't working. I'd pull it's cover off the axle and check to make sure the collar engages properly, and that the posi-lock unit travels fully and doesn't bind, etc.

The collar might not be fully engaging due to prior abuse to the unit. If the the two shafts are spinning at different speeds and someone tries to jam the CAD to engage, the splines take a beating. They aren't designed to be slipped like some kind of clutch.

I guess it could be the transfer case too, but I'd take a close look at the CAD first unless the transfer case is giving you any obvious signs (noises, grinding, etc).

Oh, and did you just stop one tire at a time with your hands...??? The front diff is an open diff so you can actually have one tire stopped and the other going and the system is fine. I don't recommend trying to have you and a buddy grab both at the same time. That'll just get someone hurt.

 

Thanks for the reply man. I have been busy with work and haven't gotten a chance to look at it again. hopefully I will get a chance to look at it this weekend.