no. 4wd is controlled by your t-case and only
your t-case. this mod simply takes the 2-piece shaft and makes it essentially a 1-piece shaft. Jeep did away with the silly CAD design in the early 90s and all Jeeps since have come with a 1-piece shaft.
the only downfall is that if your front driveshaft ujoints are bad, they will vibrate at speed. not really a downfall though, since if they need to be replaced, you should replace them.
-88 MJ; 4.0L, ex-2wd, TJ ax15/231, 78 Ford D44 w/spool, 9" w/posi, 33" trXus MTs, custom roll-bar/bumpers/etc.
Also an 86 MJ Metric ton and 2 '90 MJs
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