2-speed rear axles

A 2-speed rear axle can eliminate the need for an auxiliary transmission in some applications. These axles contain gearing for two ranges. Single reduction gearing for highway speeds and planetary double reduction gearing for high torque, deep-hole pulling power off-highway

Dana offers this product in a 46K rating: DT463, and a 52K rating: DT521. Both are approved for up to 160,000 lbs. GCWR on-highway and 140,000 lbs. GCWR for on/off-highway. They permit more GVWR (axle loaded weight) with the 52,000 lb. version, but no more GCWR (pulling weight).

Ratio combinations are as follows:

DT463-P DT521-P

3.70/5.04       4.56/6.20

3.90/5.31       4.88/6.64

4.11/5.60       5.43/7.39

4.33/5.90       6.17/8.40

A hand-operated toggle valve sets an air shift system into action to change ranges (pictured above). You can use the dash switch to toggle between the axle gearing sets on the fly, as long as the diff lock/interaxle diff is not engaged  (and you shouldn't be driving around with the interaxle engaged).   It does not require the chassis to stop prior to changing ranges.

An important note on these axles, they cannot be utilized with Differential or Cross Locks (side to side axle locking). The extra set of gearing occupies the space in the housing where this function would exist. There may be some aftermarket solutions for limiting axle spin.

And now…

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