Transfer case vacuum switch -
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Unread 06-06-2013, 08:11 PM   #1
Registered User
1991 YJ Wrangler 
Join Date: Apr 2009
Location: Greenville, SC
Posts: 157
Transfer case vacuum switch

91 YJ
AX-15 / NP-231

Just replaced the transmission, t-case, clutch. (with parts from a 1993 an assembly)

With the new (to me) tranny/t-case installed jeep will not go in 4WD.

Went in fine before the swap (so it's not the CAD)
The only thing I can think of is the transfer case vacuum switch...How do I replace it with the one from my original t-case?

Is it just unplug the vacuum block, screw the switch out, screw the other one in, and plug vacuum block back in....or is it more than that??

4WD gearing is right (in low) but the front axle is not locked in. Front drive shaft is locked to the t-case when in 4WD, but not locked to the front axle...and no 4WD light on the dash (the bulb works)

Character is Who You Are When Nobody Is Looking!!


Last edited by dswi; 06-06-2013 at 08:13 PM.. Reason: spelling error
dswi is offline   Reply With Quote Quick reply to this message
Unread 06-06-2013, 08:35 PM   #2
Registered User
1987 YJ Wrangler 
Join Date: Mar 2008
Location: corpus christi, texas
Posts: 7,055
Yes, unhook lines, unscrew, screw other in, replace lines. And the lines should be on a large plug so its actually just unplug one deal.
I don't feel like working on anything, at this time.
superj is offline   Reply With Quote Quick reply to this message

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