1997 Dodge 1500 4wd not working-

Ok,
My Brother in law has a 1997 dodge 1500 4wd that will not 4wd. No apologies needed, just a hand please.


I suspect the silly vacuum actuator on the front axle, as even when manually shifted to 4wd, the light will not come on, nor will the front catch. The acutator arm is also the switch actuator, so I think I am on to something

I did a bit of looking around, and could not find a good internet answer for my question, so I will open my mouth while you feed me-

What , where, when does the switching for the vacuum to the actuator? Where is the vacuum source point? Point me in the right direction and I bet I can get my head around it.

Thanks!

 

[jrgaylor]

This is a old thread but may help someone some day.
On my 2500 the transfer case is a manual shift with vacuum operate front axle.
Engine vacuum comes from the engine to the rear of the transfer case where there is a valve/selector on the top of the transfer case that has a total of 4 lines going to it, two of these go to the front axle. It is not uncommon the the actuator in the front axle to get fouled up and is where 90% of the problem is at. There is aftermarket parts to converter the front axle to a manual cable operation.