Engine/Transmission (1994 - 1998) 4x4 vacumm line routing

[budnate]

did some searches and I cant find anything here... and cant find my manual on the disc right at the moment... . doh!



anyone happen to have or recall a link to 4x4 vacumm line routing on the auto trans up to the front axel..... I want to hand trace all the lines and make sure there plugged in right, I think my Cad crapped out but the truck has had a trans done also before me and question the lines on the transfer case as being on right and want to try and do the trouble shooting right.



Thnx B.

 

[Bob V]

The four colors are gray-vacuum in, Green-vent, black-CAD engage(4WD), red-CAD disengage (2WD). Check the connector at the top of the transfer case, it might loose or installed incorrectly

 

[budnate]

Thnx Bob,



I found some old threads about the transfer case switch but saw no pictures of one installed right.



I should be able to pull the plug and feal suction on the lines with my finger at the axle when I shift the transfer case back and forth right?



B.

 

[WilsonF]

Yes, that's the way I checked mine.

Floyd

 

[JDKammin]

If you have vacuum to the front axle, pull the four 1/4" bolts out of the CAD shift cover and remove it from the axle. Start the truck up and have someone shift in and out of 4WD. The fork should slide back and forth. Make sure there are pads at the each end of the fork. If you do not have vacuum at the axle, you can remove hoses at the transfer case end of the steel lines and see if you have vacuum there. I had on guy's truck that had to replace the steel lines, since they rusted thru. Another truck had a bad rubber connector that goes onto the transfer case switch. That rubber connector will only go onto the transfer case switch, one way. Make sure the vacuum line between the engine and the brake booster is connected. There is a tee connector that the vacuum line comes off of and goes to the transfer case.

 

[budnate]

thnx guys, going to crawl under it this weekend.



B.

 

[budnate]

lines look ok, either the cad is iffy or the transfercase switch is iffy. . I can have the pass front tire off the ground and shift the transfer case and after a little wiggling sometimes at the cad or it just feals like it, it will lock up in 4x4.



I dont know if I get a delay from the switch being stiff from non use or the cad is weak or gummed up inside... .



I bought both new from ebay... . question on the transfer case switch, how does it mount? threaded? bracket holding it in?



dang truck is just far enough off the ground you have to be up on your elbow to barely see the lines and cant see how it mounts? wondering how fast it will swap out?



Thnx B

 

[PToombs]

Bud, it screws in. Either 1 1/16 or 1 1/8, IIRC, you need a 12 point deep socket. (don't quote me, it's been 3-4 years) You can verify when your new switch gets there. I just pull the hose, throw the socket on, and give it a yank. It should screw out by hand after that. When you put the hose unit back on, notice what direction the grooves are, there are 2 tabs on the switch that mate with 2 grooves on the rubber plug.

About 10 minutes, maybe 15 if it's your 1st time.

Good luck!



PS, try to blow the area off with air, dirt lays right around the switch. pt

 

[budnate]

Pete, waiting on the parts still, thnx for the heads up.



B.

Bud, it screws in. Either 1 1/16 or 1 1/8, IIRC, you need a 12 point deep socket. (don't quote me, it's been 3-4 years) You can verify when your new switch gets there. I just pull the hose, throw the socket on, and give it a yank. It should screw out by hand after that. When you put the hose unit back on, notice what direction the grooves are, there are 2 tabs on the switch that mate with 2 grooves on the rubber plug.

About 10 minutes, maybe 15 if it's your 1st time.

Good luck!



PS, try to blow the area off with air, dirt lays right around the switch. pt

 

[budnate]

FIXED IT!!, just a FYI, found a hole in the black plastic line about 2" back from where the lines connect to the metal vacuum lines on the passenger frame rail, back inside under the split loom, crazy!..... took some time looks like it was melted with something hot, about 3/16 hole, so that's why it is was so slow to pull in, man that was a bugger to find. slams in with authority now, Miller time.



a hand held vacuum gauge is your friend, it will show where your weak signal is, by finger you cant tell very accurately.



one other thing I will add as I did not read it anywhere in my search to sort this out and would have helped me the first time I went under the truck.



, the red line is what holds you out of 4x4 and the black line pulls the cad over to lockup the front axel.



jack up the pass front tire and shift the transfer case back and forth with the motor idleing and spin the tire, when in 4x4 it will lock up with hardly a spin of the tire if your not locking up your tire you are not getting vacuum to the cad or the cad is toast poke around with your gauge and see if you have 20" on the black line everytime you shift into 4x4 its your cad if you do, if your not seeing vacuum your open somewhere or the transfercase switch is hung up.

and not passing vacuum through it.



also zip tie all your rubber connections mine are getting sloppy from old age and I am pretty sure were weeping vacuum





peace, B.