Chevrolet Repair: front diff on 92 chevy, castle nuts, ball joints

Question
QUESTION: when in 4 wheel ,when you step on gas truck pulls to the right . when you let off the gas jerks back to the left. it has new balljoints and has been aligned. its fine when 4 wheel not engaged. doesn't do this .

ANSWER: GOOD MORNG DANIEL,,CK YOUR LEAFSPRING MOUNTS,, SOUNDS TO ME LIKE THE FRONT AXLE IS SHIFTING TO THE RIGHT CAUSING THIS PULL. GET A BAR ON THE SPRING PURCHES AND MOUNTS MAKE SURE THEY ARE ALL TIGHT...I KNOW YOU SAID BALL JOINTS ARE NEW, BUT MAKE SURE THE CASTLE NUTS ARE TIGHT AND BALL JOINTS ARE SEATED IN THE KNUCKLE..JUST A SLIGHT SHIFT WILL CAUSE THIS PULL. LET ME KNOW HOW THIS GOES AND GET BACK TO ME..GOOD LUCK,, TOM..

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QUESTION: this truck is a half ton with upper and lower control arms. evrything is good and tight seems like. it doesn't jump around in the road when you have it in two wheel drive. it drives good then . wear on the front tires is pretty even to.

Answer
HI DAINEL,YES ,IAM SORRY ABOUT THAT I THOUGHT I READ 82...HAVE YOU TRIED TO JACK THIS UP BY THE LOWER CONTROL ARMS AND CK FOR ANY BUSHINGS THAT MAY HAVE SOME PLAY IN THEM..THEN JACK THIS UP WITH THE CONTROL ARMS FREE HANGING. PUT A BIG BAR BETWEEN THE CONTROL ARM AND FRAME AREA AND SEE IF YOU SEE ANY MOVEMENT..TRUST ME WHEN I SAY THIS, WILL  TAKE 1/4 TO 3/8" OF MOVEMENT TO MAKE WHAT IS HAPPENING TO THIS TRUCK. FOR THIS TO ONLY HAPPEN IN 4WD THIS IS A TORQUE RELATED PROBLEM. CALLED YOU GUESSDED IT [TORQUE STEER.] SO IF THE WHEEL ON THE LEFT SIDE IS SHIFTING FORWARD OR THE WHEEL ON THE RIGHT IS SHIFTING BACKWARDS THIS WILL CAUSE THIS.. TRY THIS,,PUT IT IN 4WD AND HAVE A FRIEND WATCH THE LEFT AND RIGHT FRONT WHEEL FOR ANY KIND OF SHIFTING PROBLEM IN THE WHEEL AREA,,LIKE A JUMP IN THE WHEEL WHEN GIVING IT FAST THROTTLE TAKE OFF ..THIS WAY YOU WILL KNOW WHAT SIDE TO REALLY CK OUT..HOPE THIS HELPS YOU, IF NOT GET BACK TO ME AND GOOD LUCK TO YOU..TOM