Trac-Lok/Power-Lok Operation

In a conventional differential, if one wheel spins, the opposite wheel will generate only as much torque as the spinning wheel.
The 248 RBI axle is optionally equipped with a Trac-lok differential while the 267 RBI axle is optionally equipped with a Power-lok differential. Both differentials achieve the same results through slightly different means.
In the Trac-lok and Power-lok differentials, part of the ring gear torque is transmitted through packs which contain multiple discs. The clutches will have radial grooves on the plates, and concentric grooves on the discs or bonded fiber material that is smooth in appearance.

Fig. 3:

In operation, the Trac-lok and Power-lok clutches are engaged by two concurrent forces. The first being the preload force exerted through Belleville spring washers within the clutch packs. The second is the separating forces generated by the side gears as torque is applied through the ring gear.
The Trac-lok and Power-lok designs provide the differential action needed for turning corners and for driving straight ahead during periods of unequal traction. When one wheel looses traction, the clutch packs transfer additional torque to the wheel having the most traction. The Power-lok differential additionally utilizes a ramping action supplied by the cross shafts to increase the force applied to the clutch packs to increase the torque supplied to the non-slipping wheel. Trac-lok and Power-lok differentials resist wheel spin on bumpy roads and provide more pulling power when one wheel looses traction. Pulling power is provided continuously until both wheels loose traction. If both wheels slip due to unequal traction, operation is normal. In extreme cases of differences of traction, the wheel with the least traction may spin.