just bought a grand wagoneer 88'. it has a 360, 727, and i think a NP229? not sure about the t-case but thats what it looked like on the tag. any info on the t-case would be greatly appreciated. info like the quality, reliability, or if a NP229 even exist? the local dealership isnt much help unless i want to buy a NEW vehicle.  

The NP 229 AKA Selectrac...

*Found this at..
http://wagoneers.com/FSJ/tech/TransferCase/Selectrac-NP229-info.html

This is the transfer case range selector.  High is for normal use, low
when you need to put mega power to the wheels, albeit at a much slower pace!
I have an '85 GW w/ 360 engine, automatic trans & select trac with the
lever on the floor and I'm assuming you have something similar.  According to
owners manual, you have to follow a particular patern to shift, so I'll quote
rather than try to paraphrase (my appologise for the the length):

       Selec-Trac Provides:
       - Either 2- or full-time 4-wheel drive in HI range;
       - An N (Neutral) position to disengage the axles from the powertrain
       - Part time four-wheel drive in LO range.

       Because selec-trac control functions are interrelated, mode
       switch and range lever must be used in specific combinations
       to operate the transfer case.

       With range lever in the HI range, select either 2-wheel drive
       (2WD) or full time 4-wheel drive (4WD) by moving the mode switch.
       Mode selection can be made *WHILE THE VEHICLE IS MOVING
       AT ANY LEGAL SPEED.*

       NOTE:  If mode switch is moved from one position to another
       while the vehicle is not moving, it may be necessary to move
       the vehicle forward or backwards slightly for the transfer case
       to fully engage 4WD, expecially in cold weather.

       If mode switch is in 4WD and the transfer case has completed
       the shift, Selec-Trac offers a choice of HI, N, or LO rnages
       by moving range lever.  Range shifts must be made *ONLY AT
       LOW SPEED 2-3 MPH, 3-5 KM/H)*.
       
       CAUTION:  Never attempt to engage LO range when vehicle
       is in 2WD or when vehicle is moving faster than 2-3 mph (3-5
       kmh).  Transfer case damage may result.
       
       *WARNING:  NEVER PARK YOUR VEHICLE WITH RANGE LEVER IN THE
       N (NEUTRAL) POSITION.  THE VEHICLE COULD ROLL UNEXPECTEDLY
       EVEN IF AN AUTOMATIC TRANSMISSION IS PLACED IN PARK OR A
       MANUAL TRANSMISSION IS IN GEAR.*

       Mode Selection (2WD/4WD)
       Mode switch allows you to select 2WD or 4WD whenever you
       wish, as long as range lever is in the HI range position.

       NOTE:  Complete transfer case engagment into HI must be
       made before you can or should attempt to engage 2WD.

       Range Shifts (HI-N-LO)
       Range lever allows you to shift to HI, N, or LO range when
       the transfer case is fully engaged in 4WD, the vehicle is
       moving slowly (2-3 mph) and the *TRANSMISSION* is shifted
       to neutral.
       
       CAUTION:  Do not try to move range lever from HI to LO when
       mode switch is in the 2WD position.  The range lever shift linkage
       could be damaged.

       - HI position
       2WD or 4WD--In either position, the vehicle may be operated
       on all road surfaces.  In 4WD, Select Trac offers better traction
       when roads are wet, snow covered or icy.  Use Selec-Trac
       4WD year-round (full time) if you wish.

       - N Position (Neutral
       In this position the axles are disengaged from the powertrain.
       The vehicle may be towed without removing the propeller shafts.
       Place an automatic transmission in Park or a manual transmission
       in gear afdter the N position is engaged

       - Lo Position
       This position provides 4WD for occasional use when *OFF-ROAD*
       driving conditions require low speed pulling power.