Received my GM Vacuum Switch today and got everything ready to install. First time I could not find the thing! Know it is on top of the transfer case. Came in house and watched YouTube which showed where it was. Went back out and found the switch. Now for the life of me I can not figure out how to get my big hands up in there to get it out! Any suggestions from anyone who has done it will be greatly appreciated.

 

You won't be able to see it, but try going at it from the back side of the transfer case.

 

it's a PIA to do but you can gain a couple inches of room by removing the trans mount completely and lowering the trans onto the cross member

 

I used a regular7/8 wrench and reached up and found the vac switch blind unhooked the vac lines, cleaned around switch,put wrench on switch and changed it out. Try using your other hand to get the right angles for access. It is a contortionist kind of repair.

 

I just did this on my 2003 and was helped by the You tube vid's. I was the one who posted them on my original forum post. The best way to access it is to get under the truck at the driver's door. you need a good shop light that is compact. You need a 7/8" wrench. One of the vid's suggested a 22 MM stuby wrench, but the conversion /inch to metric/ told me the MM size is 22.25 and that tells me the 22 mm wrench should be too small. So that means a 23mm! I went with the 7/8 " and so I used that. Slide under at the driver's door and grab the torsion bar and look up at the transfer case. You can barely see the top of the switch and the three vac. hoses in a single rubber connector. CLEAN the area around the switch before you start the removal of the switch. If you don't have a compressed air gun, use WD-40 and a shop rag and a nylon brush. Remove the connector and push it up and out of the way. The light has to be attached.....you cannot hold it with the other hand. Now be patient. You can only move the wrench a small amount at a time. Flip over the open end of the wrench and grab the 'flats' on the old vac. switch. Move the wrench and remove it and reinstall it and move it a little and flip it each time. Be patient and careful to grab the flats and not the hoses especially when you re installing the new one. Use the 'O' ring on the new one. Note the key on the switch to make sure that the switch is correctly positioned with the three hose connector. IOW it can only go on one way.