Hey all!!

The 4WD vacuum selector switch on top of my transfer case is broke internally. And it’s incredibly rusted in place and won’t come off without me likely pulling the t case off which I don’t want to do right now cause I’m working a lot of hours at work and it’s cold. As of right now when I need 4x4 I just hop under the truck and swap the red and black vacuum lines and it locks the front driveshaft no problem.

ive seen the traditional cable bypass but I don’t want to buy the kit and don’t really want to mess with my CAD

I saw the video below but don’t know what exactly to buy.... ideally u just want some kind of multi way vacuum switch toggle to enable / disable 4WD...

 

Just leave the front axle locked. Transfer case is what routes power to the front axle. You may lose a point in fuel mileage, but, you will have 4x4 when you need it.

 

yea but what about when the road is dry? My objective was to still be able to use 4WD on and off on demand

 

Doesn't matter. So long as the t-case isn't in 4x4, no power is being transmitted to the front axle. Everything just freewheels.

 

ok so I’m confused. If I switch my vacuum lines and it says 4WD on my dash I can still drive it on pavement?

 

The 4x4 lite is activated by the switch on the CAD. What it really means is the passenger side axle is locked together. You don't actually have 4x4 unless the t-case is shifted to some variety of 4x4. (hi or lo) In 2wd, the front driveshaft isn't powered. So, with the front axle locked, things will spin, but, they won't be powered. Of course, under normal circumstances, (and proper operation) the CAD won't be locked UNTIL you put it in 4wd, and you don't actually HAVE 4 wheel drive UNTIL the lite comes on. With the t-case in 4wheel drive, but the lite NOT on, any power sent to the front axle is pretty much wasted, as it just spins that intermediate axle on the passenger side, since there is zero resistance to it turning.

The problem you run into using 4 wheel drive (with the t-case in 4lo or hi) is the front and rear travel different distances in turns, so, unless one end or the other is able to slip a bit, like they can in snow/mud/dirt/ice/grass/whathaveyou, you starting putting things into a bind, and eventually, the truck stops moving altogether, or, something breaks. (and the truck stops moving.....)

 

ok thanks for the explanation. So, if my floor shifter is still in 2wd but I swap the vacuum lines and the 4WD light comes on and I can feel the front driveshaft locked does that mean I’m still NOT in 4WD unless I actually move the floor shifter into 4hi?

 

Correct. The T-case determines how many drive wheels you get.

 

AAHHHHH OKAY! So to make sure I’m getting this right.

1. the vacuum lines switched (4WD light on)
+
2. The floor shifter in 2wd
= still only in 2wd (the front driveshaft being locked just means it’s spinning freely)

OR

1. The vacuum lines switched (4WD light on)
+
2. the floor shifter in 4HI
= Actually in 4x4

So doing this should still allow me to shift between 2wd and 4HI on the fly as normal right?

on another note; hope you are doing well friend! We made it up to our place in the UP a few months back and it’s been fun. Sunshine and 70F one day and 3 inches of snow the next day

 

Correct! Not to mention you'll have 4wd faster as the cad doesn't have to engage. I got rid of my cad a while ago lol