With an assistant on the opposite side, start the installation test by rotating both wheels in a forward direction as far as possible. (Both wheels should stop after rotating a short distance.)
Section 05-02F: Differential, Dana Model 80 Locking Axle | 1996 F-350 Super Duty Workshop Manual |
Installation Test
With the engine turned off, raise driving axle(s) until all wheels are out of contact with any surface.
Place the transmission (7003) in gear or park so that driveshaft does not rotate.
With an assistant on the opposite side, start the installation test by rotating both wheels in a forward direction as far as possible. (Both wheels should stop after rotating a short distance.)
With an assistant firmly holding the right wheel forward (against the stop), rotate the left wheel rearward while listening for an indexing or clicking sound. (The right wheel must be held firmly against the stop or the left wheel will not disengage freely.) Grasp the left wheel to stop its rotation and move it slightly forward (in the direction of the stop). The Detroit Locker® differential should lock up.
Rotate both wheels rearward as far as possible. (Both wheels should stop after rotating a short distance.)
With the assistant on the opposite side firmly holding the right wheel rearward (against the stop), rotate the left wheel forward, again listening for an indexing or clicking sound. (Again, the right wheel must be held firmly against the stop or the left wheel will not disengage freely.) Grasp the left wheel to stop its rotation and move it slightly rearward (in the direction of the stop). The Detroit Locker® differential should lock up.
REPEAT STEPS 3, 4, 5 and 6, except hold the left wheel against the stops and rotate the right wheel in both forward and reverse.
If the above steps are completed successfully and the rotating wheels disengage easily by hand, rotate freely and evenly, and produce a faint indexing or clicking sound, then the Detroit Locker® is properly installed and is functioning correctly.
IF EITHER WHEEL DOES NOT ROTATE FREELY IN EITHER DIRECTION, recheck each installation step. Also, check hand and foot brakes for possible drag caused by improper adjustment. If differential (4026) is still not operating properly, replace or repair as necessary.
Operation Test
Check to see that both wheels of each Detroit Locker® differential-equipped axle are driving. Make this test under load, so that engine torque is applied through the Detroit Locker® differential with the wheels on the ground. One way to achieve this load is to drive up against a solid obstruction (on loose dirt or gravel, if possible) and attempt to spin both wheels together. Perform this test in forward and reverse. (Exercise caution when performing this test to avoid damage to vehicle or obstruction.)
CAUTION: Do not operate the vehicle if both wheels of a Detroit Locker®-equipped axle are not driving. Power to only one wheel can cause serious steering problems and loss of vehicle control, and result in a mishap which can cause property damage, injury, even death.
CHECK CAMMING ACTION. On a flat surface, with good traction, drive the vehicle in a tight circle in forward and reverse to be sure that the outside wheel is free to overrun (i.e., that the outside tire does not scuff). A clicking or indexing sound may be heard. The sound of gear re-engagement may also be heard upon completion of the turn. This is normal.