OK guys, I've already traced the lines and tried checking for leaks, and it turns out I'm not getting any vacuum at all. Please help

It's a 97 2500 cummins

 

Do you have Vacuum into the transfer case switch? ( From the cowl junction block )

 

It doesn't feel like there is.

 

Ok, then start at your vacuum pump drivers side of the engine and trace the line back to the cowl on the drivers side, it comes into a Tee that splits it to the various locations. It is probably unhooked somewhere along the line.

I don't suppose your heater is stuck on defrost by any chance is it?

 

No it's not stuck on defrost. It's getting late now, I'll let you know tomorrow. Thanks

 

Might have found something here. Is there any way i can send pictures?

 

Alright, I've fixed the vacuum issue. I've got vacuum going through both lines. Not both at the same time of course. But the front end still isn't locking. What do you think?