Working on a 99 TB, the 4x4 vacuum lines are in pathetic shape and will start replacing today. I don't understand what I am seeing compared to what I have been reading here... I have NOT been under the truck yet, this is just an up top observation.

I removed the battery tray and located the actuator; it moves freely but have not tested it with power yet. Began tracing vacuum lines there. Instead of trying to describe what I see, I attached a drawing to reference... What I am confused about is:

1) What is the device on the firewall with two vacuum lines and two wires? Some kind of switch or solenoid?
2) Any idea why a vacuum hose would be running into the drivers side fender well area? I cant see behind there yet; it's buried behind the (I think ABS crap).
3) The line going into a big loom and into the firewall is a different kind of line... it's almost like hard plastic and much smaller diameter. Does this sound correct?

 

1) Vacuum switch for the auto 4x4 case
2) Vacuum canister inside the drivers side fender
3) Vacuum line for the hvac controls

 

Okay, so I got all the 4x4 related vacuum lines under the hood replaced. I crawled underneath and did not see a switch on the T-case with three vacuum lines, but there is something on top in the rear that I cant even really see. So, does the switch I described on the firewall replace the switch on the T-case, or is that what I can barely see?

After replacing all the vacuum lines I went for a short drive. I tested the switching of 4 low to 4 high and automatic, that seems to work okay, however, after driving a bit in auto and 4 high (on gravel), I had a hard time getting it out of 4x4, any ideas? I finally did get it out of 4x4, but not sure what the combination was...

 

On a 99 TB is this the correct routing for the vacuum hoses? I recently replaced vacuum lines and question my memory. It appears in this picture the hose on the top port runs to the actuator under the battery. However, I believe I googled another picture and it showed the opposite. Does it matter?

http://i115.photobucket.com/albums/n...t/DSC03018.jpg

Thanks!

 

yes it is important to have these correct. the port to the actuator vents when deenergized. the other does not

 

So I'm pretty sure these hoses were hooked up backwards when I bought it... What would be the consequences of that? Any damage to check for or anything to reset? Thanks!

 

If the hoses are reversed the transfer case should disengage when 2hi is selected, but the front axle may not if its holding vacuum. Not sure what if any damage could result.