Pinion Bearing Preload and Final Depth Check
1. Assemble pre load shims and spacer or slinger (if used) onto pinion. Assemble bearing cone and roller assembly, using T75L-1165-B, Axle Bearing/Seal Plate and T75L-1165-DA, Axle Bearing/Seal Replacer for Model 60 axles or T53T-4621-C, Pinion Bearing Cone Replacer for Model 70 axles. For Model 80 axle use D8OT-4200-B, Pinion Bearing Cone Replacer.
2. Assemble end yoke, washer and new pinion nut on the pinion shaft. Tighten nut to 325-406 Nm (240-300 ft-lbs) for Model 60 and 70 Axles. For Model 80 axles tighten nut to 596-677 Nm (440-500 ft-lbs).
3. Using an inch-pound torque wrench, rotate pinion. Torque to rotate pinion should read between 2.26-4.53 Nm (20-40 in-lbs). To increase preload, remove shims from the outer pinion bearing preload shim pack. To decrease preload, add shims.
The following illustration shows the arrow in the pinion pointing in two directions. The direction pointing towards the end yoke indicates that by removing pinion position shims, the distance from the centerline of the axle to pinion button is increased giving a plus reading. The pinion bearing preload shim pack does not affect the pinion depth setting. Arrows on the ring gear illustrate the method to increase or decrease backlash and differential bearing preload.
The following final depth check may only be performed if the button end of the pinion is a finish ground surface as defined earlier in step 11 of the differential assembly sequence. If the button is not finish ground, the proper pinion position can be verified by the gear contact pattern method outlined at final assembly instructions lust before installing the cover.
4. Install the Gauge Tube D8OT-4020-F48 for Model 60 and Model 70 axles. Use D81T-4020-F51 for Model 80 axle. Install bearing caps and bolts and tighten to 109-147 Nm (80-90 ft-lbs).
5. Insert the Final Check Gauge Block, D81T-40-20-F54 for Model 60 axles or D81T-4020-F55 for Model 70 or D81 T-4020-F56 for Model 80 axle on top of the pinion button under the Gauge Tube. Place thumb on the Gauge Block to make sure that the block is level.
Insert feeler gauges or shims between the gauge tube and the Final Check Gauge Block until a slight drag is felt.
The reading should be 0.5 mm (0.020 inch) added to the drive pinion etching, which could be plus + or minus - with a tolerance (+/-) of 0.050mm (0.002 inch).
For example: a drive pinion with a -2 etching would have a 0.45mm (0.018 inch) distance and a tolerance of 0.050mm (0.002 inch), would require 0.40-0.50mm (0.016-0.020 inch) amount of shims.
If the distance must be increased, remove shims from beneath the inner pinion bearing cup. If the distance must be decreased, add shims beneath the inner pinion bearing cup.
6. With the drive pinion at the correct depth, remove the yoke with Holding Tool, T57T-4851-B and Yoke Remover, T65L-4851-B for Model 60, 70 and 80 axles. Remove the yoke, nut and washer.
7. Coat the oil seal with grease. Install the drive pinion oil seal with Oil Seal Replacer, T56T-4676-B (Model 60 and 70). For Model 80 axle use Pinion Seal Replacer T88T-4676-A. After installation, make sure the garter spring did not pop out. If the garter spring pops out, remove and replace seal.
8. Install the yoke with Pinion Flange Replacer, D81 T-4858-A for Model 60-70 axles to draw the drive pinion up to engage the nut. Install the washer and nut and tighten nut to 339-366 Nm (250-270 ft-lbs). For Model 80 axles, tighten to 440-500 ft-lbs (596-677 Nm). Use pinion flange replacing tool T88T-4851-A.