7.5 Inch Ring Gear
PINION BEARING CUP INSTALLATION
1. Install the new pinion bearing cups with Pinion Bearing Cup Replacer T71P-4616-A. Make sure the pinion bearing cups are properly seated in their bores. If a 0.038mm (0.001 5-inch) feeler gauge can be inserted between a pinion bearing cup and the bottom of its bore at any point around the pinion bearing cup, the pinion bearing cup is not properly seated. Whenever the pinion bearing cups are replaced, the pinion bearings should also be replaced.
NOTE: To make sure pinion bearing cups will seat properly, clean bores before installing.
DRIVE PINION SHIM SELECTION
Individual differences in machining the carrier casting and the ring gear and pinion and variation in bearing widths require a pinion shim between the rear bearing and pinion head, in order to locate the pinion for correct tooth contact with the ring gear. When replacing a ring gear and pinion, the correct shim thickness for the new ring rear and pinion to be installed, is determined by the following procedure using Pinion Depth Gauge Set T79P-4020-A.
1. Place the rear drive pinion bearing cone (new or used if in good condition) over the aligning tool and insert it into the rear axle pinion bearing cup of the carrier. Place the front bearing into the front pinion bearing cup and assemble the tool handle into the screw and tighten to 27 Nm (20 ft. lbs.).
NOTE: The gauge block must be offset to obtain an accurate reading.
2. Center the gauge tube into the differential bearing bore. Install the bearing caps with the arrows pointing outward and the caps in their original locations. Tighten the bolts to 95-115 Nm (70-85 ft. lbs.).
^ Make sure that the gauge handle adapter screw, aligning adapter, gauge disc and gauge block assembly are securely mounted between front and rear bearing. Recheck tool handle torque prior to gauging to make sure that bearings are properly seated. This can affect final shim selection if improperly assembled. Clean bearing cup and differential pedestal surfaces thoroughly. Apply only light oil film on bearing assemblies prior to gauging.
^ Gauge block should then be rotated several half turns to make sure rollers are properly seated in bearing cups. Rotational torque on the gauge assembly should be 4.5 Nm (40 inch lbs.) with new bearings. Final position should be approximately 45 degrees across gauge tube to make sure that gauge block is in line with gauge tube high point. This area should be utilized for pinion shim selection. Selection of pinion shim with gauge block not lined up with tube high point will cause improper shim selection and may result in axle noise.
^ Utilize pinion shims as the gauge for shim selection. This will minimize errors in attempting to stack feeler gauge stock together or simple addition errors in calculating correct shim thickness.
^ It is important to feel a slight drag on the shim for the correct selection. Do not attempt to force the shim between the gauge block and gauge tube. This will reduce the chance of selecting a shim thicker than required which results in a deep tooth contact in final assembly for integral rear axles.
NOTE: Shims must be flat. Do not use dirty, bent, nicked or mutilated shims as a gauge.
3. Place the selected shims on the drive pinion shaft and press the pinion bearing until firmly seated on the shaft.
NOTE: The same rear pinion bearing used in this procedure must be used in final assembly of the rear axle.
DRIVE PINION INSTALLATION
1. Check splines on the drive pinion stem to be sure they are free of burrs. If burrs are evident, remove them by using a fine crocus cloth, working in a rotational motion. Wipe the pinion clean.
2. Place a new collapsible spacer on the pinion stem against the pinion stem shoulder.
3. Install the front pinion bearing and oil slinger in the axle housing bore and install the pinion seal on the Pinion Seal Replacer T79P-4676-A.
4. Clean the pinion seal seat surface. Install the pinion seal in the housing bore using Pinion Seal Replacer T79P-4676-A. Coat the lips of the pinion seal with Premium Long-Life Grease XG-1-C or -K or equivalent meeting Ford specification ESA-M1C75-B.
CAUTION: Installation without the proper tool may result in early seal failure. If pinion seal becomes cocked during installation, remove it and install new one.
5. From the rear of the axle housing, install the drive pinion assembly (drive pinion, shims, rear bearing cone and roller, and collapsible spacer) into the rear axle housing pinion shaft bore.
NOTE: Differential bearing preload and ring gear backlash is adjusted with the drive pinion and differential case installed. Adjustment is performed by the installation of shims between the differential bearing cup and axle housing.
6. Apply a small amount of lubricant to the companion flange shaft splines of rear axle companion flange. Align the mark on the rear axle companion flange with the mark on the pinion stem.
NOTE: If a new rear axle companion flange is being installed, disregard the scribe mark on the pinion stem.
UNIVERSAL JOINT FLANGE INSTALLATION
1. With the drive pinion in place in the axle housing, install rear axle companion flange using Companion Flange Replacer TOOL-4858-E or equivalent.
NOTE: The rear axle companion flange must never be hammered on or installed with power tools.
2. Start a new pinion nut. Hold the rear axle companion flange with Companion Flange Holding Tool T78P-4851-A.
3. Tighten the pinion nut, rotating the pinion occasionally to make sure pinion bearing is properly seated. Take frequent pinion bearing torque preload readings until the original recorded preload reading is obtained by rotating the pinion with an inch-pound torque wrench.
If the original recorded preload is lower than specification (used bearings .9-1.5 Nm [8-14 inch lbs.]; new bearings 1.8-3.3 Nm [16-28 inch lbs.]), tighten to specification. If the preload is higher than specification, tighten to original reading as recorded. Under no circumstances should the pinion nut be backed off to reduce preload. If reduced preload is required, a new collapsible spacer and pinion nut must be installed.
DIFFERENTIAL CASE INSTALLATION
For shim selection after a complete replacement of the axle housing, the differential or differential bearings, use the following instructions. For replacement only of a ring gear and pinion, or a backlash adjustment, follow Steps 9 through 13 and Step 15, using the differential bearing shims that were originally in the rear axle.
1. With pinion depth set and pinion installed, place differential case gear assembly with differential bearings and cups in the carrier.
2. Install a 6.73 mm (0.265-inch) differential bearing shim on left side.
3. Install left bearing cap and tighten bolts finger-tight.
4. Install progressively larger differential bearing shims on the right side until the largest one selected can be assembled with a slight drag feel.
^ Apply pressure toward left side to make sure differential bearing cup is seated.
5. Install right side bearing cap and tighten all four (4) bolts to 95-115 Nm (70-85 ft. lbs.).
6. Rotate assembly to make to free rotation.
7. Check ring gear and pinion backlash. If the backlash is 0.20-0.38 mm (0.008-0.015 inch) with 0.304-0.381 mm (0.012-0.015 inch) preferred, proceed to Step 14. If backlash is not within specifications, go to Step 10, unless zero backlash is measured, then go to Step 8.
8. If a zero backlash condition occurs, add .508 mm (0.020 inch) to the right side and subtract .508 mm (0.020 inch) from the left side to allow backlash indication.
9. Recheck backlash.
10. If backlash is not to specification, correct backlash by increasing thickness of one differential bearing shim and decreasing thickness on the other differential bearing shim the same amount. Refer to chart for approximate change of differential bearing shim.
SHIM CODE CHART DIFFERENTIAL SIDE BEARING
Number of Stripes and Color Code: Dim. A
2 - C-COAL: .3070-.3075
1 - C-COAL: .3050-.3055
5 - BLU: .3030-.3035
4 - BLU: .3010-.3015
3 - BLU: .2990-.2995
2 - BLU: .2970-.2975
5 - PINK: .2930-.2935
4 - PINK: .2910-.2915
3 - PINK: .2890-.2895
2 - PINK: .2870-.2875
1 - PINK: .2850-.2855
5 - GRN: .2830-.2835
4 - GRN: .2810-.2815
3 - GRN: .2790-.2795
2 - GRN: .2770-.2775
1 - GRN: .2750-.2755
5 - WH: .2730-.2735
4 - WH: .2710-.2715
3 - WH: .2690-.2695
2 - WH: .2670-.2675
1 - WH: .2650-.2655
5 - YEL: .2630-.2635
4 - YEL: .2610-.2615
3 - YEL: .2590-.2595
2 - YEL: .2570-.2575
1 - YEL: .2550-.2555
5 - ORNG: .2530-.2535
4 - ORNG: .2510-.2515
3 - ORNG: .2490-.2495
2 - ORNG: .2470-.2475
1 - ORNG: .2450-.2455
2 - RED: .2430-.2435
1 - RED: .2410-.2415
BACKLASH SPECIFICATIONS
Backlash Change Required: Thickness Change Required
.001 inch: .002 inch
.002 inch: .002 inch
.003 inch: .004 inch
.004 inch: .006 inch
.005 inch: .006 inch
.006 inch: .008 inch
.007 inch: .010 inch
.008 inch: .010 inch
.009 inch: .012 inch
.010 inch: .014 inch
.011 inch: .014 inch
.012 inch: .016 inch
.013 inch: .018 inch
.014 inch: .018 inch
.015 inch: .020 inch
11. Install the differential bearing shims by driving into position with Shim Driver T85L-4067-AH. Install and tighten the bearing cap bolts to 95-115 Nm (70-85 ft. lbs.).
12. Rotate assembly several times.
13. Recheck backlash. If backlash is within specification, go to Step 14. If backlash is not within specification, repeat Step 10. Backlash specification is 0.20-0.38 mm (0.008-0.015 inch). Preferred range is 0.304-0.381 mm (0.012-0.015 inch).
14. Remove bearing caps and bolts. To establish differential bearing preload, increase both left and right shim sizes by 0.006 inch. Make sure differential bearing shims are fully seated and assembly turns freely.
15. Install bearing caps and tighten bolts to 95-115 Nm (70-85 ft. lbs.).
16. Utilize white marking compound to obtain a tooth mesh contact pattern in your assembly.
Pattern inspection is intended to allow technicians the ability to detect gross errors in set-up prior to complete reassembly. Pattern contact should be within the primary area of the ring gear tooth surface avoiding any narrow or hard contact with outer perimeter of tooth (top to root, toe to heel). Pattern inspection should be on the drive (pull) side. Correct assembly of drive pattern will result in satisfactory coast performance. If gross pattern error is detected, with preferred backlash of 0.30-0.38 mm (0.012-0.015 inch), recheck pinion shim selection.
AXLE SHAFT INSTALLATION
1. Install the axle shafts.
2. Remove the oil seal replacer from the transmission extension housing. Install the driveshaft in the extension housing. Align the scribe marks and connect the driveshaft end yoke at the rear axle companion flange. Install bolts and tighten to 95-128 Nm (70-95 ft. lbs.).
SENSOR, ANTI-LOCK BRAKE INSTALLATION
1. If new rear brake anti-lock sensor is to be installed, lightly lubricate O-ring with motor oil. old rear brake anti-lock sensor is to be reinstalled, clean and blow off metal particles using compressed air. Remove and replace O-ring with a new O-ring.
^ Apply a light film of motor oil to the O-ring.
2. Firmly grasp rear brake anti-lock sensor at sides (do not install by applying force on connector) and push into axle housing, aligning mounting flange hole with threaded hole in axle housing.
3. Install hold-down bolt and tighten to 34-41 Nm (25-30 ft. lbs.).