Transfer case vacuum diagram? -
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post #1 of 4 Old 12-03-2010, 08:44 PM Thread Starter
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1990 XJ Cherokee 
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Location: Penngrove
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Transfer case vacuum diagram?

I have looked all over here and on the general internet with no luck, DOES ANYONE HAVE A VACUUM DIAGRAM FOR A 1990 WITH A NP231 T/C? I find diagrams that show a switch on the front differential but as near as I can tell that does not apply.

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post #2 of 4 Old 12-04-2010, 01:55 AM
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1988 MJ Comanche 
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post #3 of 4 Old 12-04-2010, 05:53 AM
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1990 MJ Comanche 
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Location: Prescott
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The vacuum switch is for the light and is mounted up under your coolant bottle.
There is a vacuum operated servo on the rear side of the front diff to engage/disengage the front axle.

My suggestion is this. The system was unreliable. It left many people without 4wd when they needed it most. In 1991 I believe the system was discontinued and they left the axle engaged all the time. Your fuel mileage will not suffer having it engaged all the time.

The axle can be permanently engaged and fixed forever with 1/2 hours work. No parts needed.
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post #4 of 4 Old 12-04-2010, 03:36 PM
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X2. I dumped mine and installed a mid 90s D30. Non disco and a little more modern brakes.
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