Final Assembly & Adjustment
DRIVE PINION INSTALLATION
1. Using micrometer or vernier gauge, measure and record thickness of original shim pack.
2. Check P.C. number on original pinion. If number is positive, subtract it from original shim pack thickness. If number is negative, add it to original shim pack thickness. Record resulting value.
3. Check P.C. number on new pinion. If number is positive, add it to value obtained in step 2. If number is negative, subtract it from value obtained in step 2.
4. Figure obtained in step 3 indicates thickness of new shim pack to be used.
5. Position correct shim pack between pinion cage and carrier. Use a minimum of 3 shims per pack. If pack is made up from various thicknesses of shims, place thinnest shims on either side of pack.
6. Install pinion and cage assembly with shims into carrier and tap into position with soft mallet.
7. Install pinion cage cap screws, torquing to 35 ft. lbs.
DIFFERENTIAL CASE INSTALLATION
1. Temporarily install bearing cups, threaded adjusting rings if used, and bearing caps, torquing cap screws to 115-140 ft. lbs.
2. If bearing cups are not of a hand push fit in bores, bores must be reworked with a scraper or emery cloth until a hand push fit is obtained. Use a blued bearing cup as a gauge and check the fits as work progresses. When cups fit properly, remove bearing caps.
3. After checking related parts, coat differential bearing cones and caps with rear axle lubricant.
4. Place cups over assembled bearing cones and position differential assembly in carrier.
5. Insert bearing adjusting nuts and turn hand-tight against bearing cups.
6. Install bearing caps in correct location as marked and tap lightly in position. If bearing caps cannot be properly seated bearing adjusters may be cross-threaded. Remove bearing caps and reposition adjusting nuts as needed. Do not force bearing caps into position as carrier, caps and adjusting nuts will be damaged.
7. Install bearing cap bolts or nuts and washers, if used, then torque fasteners to 115-140 ft. lbs.
Fig. 8 Side Bearing Preload Adjustment:
Fig. 9 Ring Gear & Pinion Backlash Adjustment:
SIDE BEARING PRELOAD & BACKLASH ADJUSTMENT
1. Using dial indicator at back face of ring gear, Fig. 7, loosen bearing adjusting nut on side opposite gear only enough to notice endplay on dial indicator.
2. Tighten same adjusting nut only enough to obtain zero endplay.
3. Check gear for runout. If runout exceeds .008 inch, remove differential and check for cause.
4. Tighten adjusting nuts one notch each from zero endplay to preload differential bearings.
5. Mount dial indicator with plunger contact bearing against ring gear tooth, Fig. 8.
6. Hold pinion and rock ring gear, reading backlash from dial indicator.
7. If backlash is not within specifications, adjust as follows. If ring gear and pinion are reused, lash should be adjusted to value measured prior to disassembly.
a. If backlash is greater than specified, loosen nut in ring gear tooth side and tighten opposite nut an equal amount.
b. If backlash is less than specified, loosen nut on back side of ring gear and tighten nut on gear face side an equal amount. Adjusting nuts must be rotated equally, in opposite directions, in order to maintain proper side bearing preload.
8. Install adjuster locks to secure adjustment.
Fig. 10 Gear Tooth Contact Inspection:
GEAR TOOTH CONTACT INSPECTION
1. Ensure that ring gear is clean and free from oil, then coat coast and drive face of each ring gear tooth with suitable marking compound.
2. Brake ring gear to ``load'' gears, then turn pinion in order to rotate ring gear one full revolution in each direction. Satisfactory contact pattern cannot be obtained unless gears are ``loaded.'' Excessive rotation of gears is not recommended.
3. Inspect tooth contact pattern referring to Fig. 9, and correct assembly adjustments, as needed to obtain correct pattern.
4. Clean marking compound from gears.
THRUST SCREW INSTALLATION & ADJUSTMENT
1. Remove carrier from stand and position with back face of hypoid or spiral bevel gear upward.
2. Remove thrust screw and locknut.
3. Install thrust screw and locknut and tighten thrust screw enough to locate thrust block firmly against back face of hypoid gear.
4. Loosen thrust screw 1/4 turn and lock securely with nut.
5. Check to ensure minimum clearance of .10 inch during full rotation of bevel gear.
DIFFERENTIAL CARRIER, INSTALLATION
1. Ensure that housing is clean and free from dirt and foreign material.
2. Inspect housing for damage and distortion, and repair or replace as needed. Remove burrs from machined surfaces using suitable stone or file.
3. Install new gasket over housing studs. If RTV sealer is used, ensure that both mating surfaces are clean and free from oil, then apply a continuous bead of sealer, 1/8 inch wide, completely around one mating surface, circling all bolt holes or studs.
4. Raise carrier assembly with suitable jack, roll assembly onto studs, then install 4 evenly spaced flat washers and nuts to hold assembly.
5. Install nuts and lock washers on any studs shrouded by housing webs, then evenly tighten 4 evenly spaced nuts to draw carrier into housing. Do not drive carrier into housing by tapping flange as flange will be distorted.
6. Install lock washers under all retaining nuts, then evenly tighten all nuts.
7. Install axle shafts and connect driveshaft to companion flange.
8. Fill housing with specified lubricant.