I check and all 4 vacuum lines are hooked up to the top of the tcase. Also checked the lines at the bottom of the tcase as well as the front diff. All lines are connected. The line is securely hooked to the tree where the cruise is so I don't understand why it isn't working. The vacuum diagram under my hood says it is supposed to be hooked up where I have it.

What do I check next?

 

Start the engine, pull the connector off of the actuator on the front axle. (pay attention to which line goes where.....) You should have vacuum at the outboard port with the t-case in 2wd, inboard port in 4wd. If you aren't getting that, need to find out where you are losing vacuum. The rubber lines dry up and break, (either that, or in your case, get burned....) the steel lines that run along the frame rust.... either way, you lose vacuum.

 

Ok finally got around to looking into this problem. There is no vacuum at the actuator. I hooked the vacuum up to the green line just to see what would happen and when the shifter is in 2wd the 4wd light comes on. When I switch it to 4wd the light goes off but the front diff doesn't engage. That makes me believe the vacuum problem is somewhere in the white line that goes to the tcase. Does that make sense?

Can I just use small vacuum line to replace the entire white line or do I need some hard line like comes stock? How is it attached to the top of the tcase?

 

Check out these pictures here bud.

https://dodgeforum.com/forum/2nd-gen...-problems.html


The vac line is 4mm OD I believe. Yeah I don't see any issue using something else, other than being a PITA to route.

 

The green line is just a vent.(suppose to have a valve on the end of it) The white line goes to switch on TC. You also need the check valves in the right places also.

 

@zman -- Your picture sucks over my actual picture and description. But at least you did draw something up. hahaha

 

I did that 2 years ago for someone here. All it needs is the check valve locations. The TC switch has a rubber thing with the 4 lines going into it as you know, so that end is pretty easy as long as even a few inches of line are still on it.

 

The white and green lines had melted about a foot from the rubber thing with the 4 lines. I cut the bad part out and used some vacuum line to connect it back together. Tested it and 4wd works. Thanks Wh1t3NuKle the pictures helped a lot.

It didn't want to come out of 4wd when I tested it tho which was odd. It eventually came out but it took MUCH longer that it use to.

 

May still have a little bit of a vacuum leak somewhere.

 

There is a little bit of burnt line where they go into the 4 rubber thing. I tried to pull them out so I could replace it but I couldn't get it off of the rubber thing. If there is still a vacuum leak I'd say that's where it is.