These questions relate to the Detroit Locker®, Detroit C-Locker™, Detroit SofLocker™,NoSPIN® brands of positive locking differentials:
A first time driver of this differential will notice some differences compared to driving with a conventional differential.
Turning: An occasional snapping/metallic sound may be heard due to component dis-engagement and re-engagement; transfer of torque from both wheels to one wheel (and back to both wheels) may be noticeable in the feel of steering.
Drive-to-Coast: A metallic sound may be heard due to the normal backlash built into the unit.
Slippery Roads: Vehicles equipped with traction differentials are inherently more sensitive to side slip. Use caution when changing speed on slippery or unstable surfaces; decelerate, but DO NOT APPLY THE BRAKE.
Backlash - How Much? At the tire tread, 1" to 2" (at the driveshaft, 30o to 90o) depending on tire diameter and ring gear ratio.
"Locker" In Front Axle? Yes, if front drive can be disconnected - either from inside or outside the vehicle - while driving on hard surface roads.
Tire Pressure? Mismatched pressures mean different tire diameters and different wheel speeds. Recommendation: Keep tire rolling radius (by air pressure) matched within 1/4" for highway vehicles and 1/2" for off-road vehicles.
Remove Holdout Rings For Racing To Assure Rapid Engagement? Yes, but operation will be harsher and the unit's life may be shortened.
Weak Springs? Yes, but this is rare.
How To Tell If My Unit Is Functioning Properly? Perform these two tests:
With the engine turned off, raise NoSPIN equipped driving axle(s) until all wheels are out of contact with any surface. Place the transmission in gear or park so that the drive-shaft is locked and does not rotate. Test for forward dis-engagement:
With two people, rotate both wheels rearward, as far as possible to lock both wheels
With the left wheel securely held in the rearward direction, rotate the right wheel slowly forward. A faint indexing or clicking sound should be heard as the NoSPIN disengages on the right side.
With the right wheel slowly rotating forward, the left wheel should be rotated slightly forward. This will lock both wheels.
Again, rotate both wheels rearward, as far as possible to lock both wheels.
With the right wheel securely held in the rearward direction, rotate the left wheel slowly forward. A faint indexing or clicking sound should be heard as the NoSPIN is disengaged on the left side.
With the left wheel slowly rotating forward, the right wheel should be rotated slightly forward. This will lock both wheels.
Repeat steps 2-7 except, test for reverse disengagement.
If the above steps are completed successfully and rotating wheels disengage easily by hand, rotate freely and evenly, lock both wheels when required, and produce a faint indexing or clicking sound, then the NoSPIN is properly installed and is functioning correctly.
IF EITHER WHEEL DOES NOT ROTATE FREELY IN EITHER DIRECTION or does not lock both wheels as required, re-check the installation of the NoSPIN in the axle. Also, check hand and foot brakes for possible drag caused by improper adjustment. Be sure that all thrust washers have been removed from the standard differential support case.
To check normal NoSPIN operation, drive the vehicle on a flat surface with good traction, in a right or left 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.
Check to see that both wheels of each NoSPIN differential equipped axle are driving. Make this test under load, so that engine torque is applied through the NoSPIN 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 of obstruction.) CAUTION: DO NOT OPERATE THE VEHICLE IF BOTH WHEELS OF A NoSPIN/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.
What If One Off The Ground Wheel Is Spinning? Apply the brake a little, to give some torque transfer to allow the differential to enter its operating range.
For 2 Pinion Pair Models Used In Non C-Clip Axles, Is The Axle Spacer Required? Yes.
Why Not Use Same Model In Front Or Rear Axle? Units are assembled differently for each axle location, to match the opposite rotations.