SPROCKET 4F6676 - Caterpillar

Disassembly And Assembly Manual Corrections
In Disassembly and Assembly Manuals SENR8226, SENR8653, and SENR8213, replace Steps 13 through 15 with:
13. Screw a nut fully onto stud and use a 203 mm (8.0 in) torque wrench on the nut (10). The torque wrench MUST be in line with the center of the wheel. Rotate the wheel several turns to seat the bearing rollers against the cone back face rib. This wrench will be used to check the rolling torque of the wheel.While rotating the wheel, tighten adjusting nut (9) to a torque of 600 N m (440 lb ft) to seat the bearings and keep all rollers parallel to each other and at the same location on the cone ramp. All wheel rotation must be in the same direction.
Loosen adjusting nut (9) until hand tight, taking care not to over-loosen. Rotate the wheel two or more revolutions in the same direction as before. Measure the rolling torque. This value (D) is the rolling torque due to Duo-Cone seal drag and will be used below.
14. If a 203 mm (8.0 in) Torque wrench is used, the correct value for rolling torque due to wheel bearing preload (T) is 5.3 N m (47.2 lb in). Use the following formula to calculate the correct value for rolling torque due to wheel bearing preload if a different length torque wrench is used:T = (A x T0)/(A + B)
Where:
A = length of torque wrench (mm)
T0 = correct rolling torque due to bearing preload if measured from center of wheel (12 N m or 8.90 lb ft)
B = distance from wheel center to center of stud (257.5 mm or 10.14 in)
T = correct value for rolling torque due to wheel bearing preload if using torque wrench of length A at stud location.
Use the same torque wrench for measuring both seal drag rolling torque and total rolling torque.Using the value for seal drag rolling torque (D) in Step 13, calculate the total rolling torque [T(total)] using the formula below:
T(total) = T + D
Tighten adjusting nut (9) while rotating wheel until the total rolling torque is equal to T(total).
15. Install lock (12) onto adjusting nut (9). Invert the lock if necessary to determine the nearest locking position. Either loosen or tighten the adjusting nut (9) as needed to align the lock bolt holes with the holes in the hub. Check the total rolling torque. It should be equal to T(total) 3.5 N m (31 lb in).Specification Service Manual Module Correction
In Service Manual Module SENR8636, the Illustration and procedure on Page 36 applies only to the D300E Articulated Truck. The Illustration and procedure for the D250E Articulated Truck were omitted. The Illustration and procedure for adjusting the wheel bearings on the D250E Articulated Trucks follows:
It is important to achieve the correct preload when adjusting wheel bearings. Correct preload can significantly improve wheel bearing life in the high load, high speed application. Too much preload reduces wheel bearing life, while too little preload reduces planetary gear life. Make a