89 yj w/ax15 (NEW) NP231 (REBUILT), hpD30 front w/ new carrier & 4:56 gears and bearings, d35 w/New carrier and 4:56 gears and new bearings, posi lock delete w/ collar locked to axles. my problem is in 4low 1st gear I get horrible ratcheting noise that disconnects power to front axle. Sounds like splines and coupler not quite messing and kicking out under high torque load The more torque the worse it is.it will do it in 4high not nearly as bad. i'm thinking transfer case but would like some input from someone smarter than me!!