First check to see if the front drive shaft turns. If it turns then check for 4wd light. If no light then your vacuum shift motor is not working. On the top of your axle there is box bolted on the axle with an eletrical conector and two vacuum tubes. There are three reasons why it doesn't work. 1. There is no vacuum to the motor, check for vacuum pressure at the motor. 2. the solenoid (part where vacuum hoses connects) put about 15hg vacuum on outside vacuum port and block off inside port. With vacuum on jack up front end and try to tun drivers side tire. If drive shaft turns when you turn the wheel then problem is related to vacuum. if not then either solenoid is bad or the guide bushing inside is bad. Unbolt the shift motor and try to slide the spline conector back and forth. You should be able to push the connector over fairly easy, you might have to turn the tire a little. If it does not slide over the other axle then the bushing is bad and you'll need to pull the axle and replace. If it slides over the other axle then the solenoid is bad.
if it is a 4x4 the fork in the transfer case could be worn out to check put transfer case in 4 low and see if it works
A 1995 Dodge Ram does not have a transfer case control module. The transfer case is mechanically controlled.
On a Dodge truck, the vacuum switch is on the transfer case.On a Dodge truck, the vacuum switch is on the transfer case.
A 1999 Ram does not have a transfer case control module.
It is on the back of the transfer case, takes a 10mm Allen wrench to remove.
its on a 98 dodge ram with a manual shifter shifts fine but dose not engage
NP241...?
np231
ATFATF
Dodge didn't make a 1991 Durango.
The problem is most likely in the transfer case or the linkage. The transfer case is bolted to the rear of the transmission on that truck. The linkage could be misadjusted, there should be three distinct positions for the transfer case, Neutral, Low and High. If you suspect the linkage disconnect the linkage and manually put the transfer case in each position and try it to see if it works, if it does it's the linkage if not the problem is in the transfer case itself.
The transfer case on a 2004 Ram uses ATF+4.