'89 F250 4WD ... HD or Standard front suspension?
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The best way I know to tell the difference between the light and heavy duty is by the axles. The heavy duty will have a full floating rear end and a Dana 50 twin traction beam front end. A light duty will have the semi float rear end (no protruding hub and axle flange) and a Dana 44HD ttb front. The Dana 50 front uses one ton lock outs, 44 uses half ton lock outs...what else.....the Dana 50 hub is the same size as the center hole in your wheels, the Dana 44 necks down. That's all I can think of right now, hope that answers your question.
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