Section 05-02A: Axle, Integral Carrier—7.5-Inch Ring Gear | 1994 Mustang Workshop Manual |
DISASSEMBLY AND ASSEMBLY
Axle Disassembly
Service operations on the differential case (4204)
assembly and drive pinion assembly can be performed with
the rear axle housing (4010)
in the vehicle.
Sensor, Anti-Lock Brake
Removal
- Raise vehicle on hoist. Refer to Section 00-02.
- Carefully remove rear brake anti-lock sensor (2C190)
.

Universal Joint Flange, Rear Axle and Flange Yoke Seal Removal
SPECIAL SERVICE TOOL(S) REQUIRED
| Description |
Tool Number |
| Companion Flange Remover |
T65L-4851-B |
| Companion Flange Holding Tool |
T78P-4851-A |
| Pinion Seal Replacer |
T79P-4676-A |
Removal
Replacement of flange yoke seal (4676)
only involves removal and installation of pinion nut and rear axle universal joint flange (4851)
.
CAUTION: This operation disturbs the pinion bearing preload, and this preload
must be carefully reset when assembling.
- Raise the vehicle and install safety stands. Refer to Section 00-02. Remove
rear wheels (1007)
.
- Make scribe marks on the driveshaft centering socket yoke (4782)
and rear axle universal joint flange
to ensure proper position of the driveshaft (4602)
during assembly. Disconnect the driveshaft
from the rear axle universal joint flange
. Remove the driveshaft
from the transmission extension housing. Install an oil
seal replacer tool in the transmission extension housing to prevent oil leakage.

- Install a Nm
(lb-in) torque wrench on the pinion nut. Record torque
required to maintain rotation of the pinion through
several revolutions.

- While holding rear axle universal joint flange
with Companion Flange Holding Tool T78P-4851-A remove
pinion nut.

- Clean area around flange yoke seal
. Place a drain pan under flange yoke seal
or raise front of vehicle higher than rear.
- Mark rear axle universal joint flange
in relation to pinion shaft so rear axle universal joint flange
can be installed in same position.

CAUTION: The rear axle universal joint flange
must never be removed with a hammer.
- Remove rear axle universal joint flange using
Companion Flange Remover T65L-4851-B.

CAUTION: Do not damage rear axle housing
while removing flange yoke seal
.
- Position screwdriver under flange of flange yoke seal
and strike with hammer to wedge screwdriver blade
between metal flange of flange yoke seal
and rear axle housing
.

- Pry up on metal flange of flange yoke seal
. Install gripping pliers and strike with hammer until flange yoke seal
is removed.

Differential Case Removal
SPECIAL SERVICE TOOL(S) REQUIRED
| Description |
Tool Number |
| Differential Side Bearing Remover |
T70P-4221-A |
| Step Plate |
T81P-4220-A |
Removal
- Raise vehicle and place jackstands under rear frame crossmember. Refer to
Section 00-02. Lower the hoist so that rear axle housing
is at suitable working height.
- Remove axle housing cover (4033)
from rear axle housing
and drain lubricant.
- Perform the inspection before disassembly. Refer to Cleaning and Inspection.
- Remove rear wheels
, rear disc brake calipers (2552)
and rear disc brake rotors (2C026)
. Refer to Section 06-04.
- Working through cover opening, remove differential pinion shaft lock pin (4241)
and remove differential pinion shaft (4211)
and differential pinion gears (4215)
.

- Push axle shaft (4234)
inward until rear axle shaft retaining u-washers (4N237)
at button end of the axle shaft
are clear of side gear recess.
CAUTION: Care should be taken not to damage inner wheel bearing oil seals (1177)
when removing axle shafts
from rear axle housing
. In addition, axle shafts
should be completely removed from rear axle housing
.
- Remove rear axle shaft retaining u-washers
and pull axle shafts
out of the rear axle housing.

- Make scribe marks on driveshaft
, driveshaft centering socket yoke
and rear axle universal joint flange
to ensure proper alignment at assembly. Disconnect driveshaft
from rear axle universal joint flange
. Remove driveshaft
from vehicle. Insert an oil seal replacement tool in the
transmission extension housing to prevent leakage.

CAUTION: Bearing caps must be installed in their original positions.
- Mark one differential bearing cap to help position the caps properly during
assembly.

- Loosen differential bearing cap bolts and bearing caps.
Note direction of arrows on bearing caps. When reassembled,
the arrows must be pointing in the same direction as before removal.
- Pry differential case
, differential bearing cups (4222)
and differential bearing shims (4067)
out until they are loose in the bearing
caps. Remove bearing caps and remove differential case
from rear axle housing
. Mark the differential bearing cups
and differential bearing shims
RH and LH to prevent assembly mix-up.

- Inspect the differential bearings (4221)
and differential bearing cups
for damage. If they are worn, pitted, galled
or spalled, remove the differential bearings
using Differential Side Bearing Remover
T70P-4221-A and Step Plate T81P-4220-A. Install new differential bearings
using Differential Side Bearing Replacer
T57L-4221-A1.


Drive Pinion Removal
SPECIAL SERVICE TOOL(S) REQUIRED
| Description |
Tool Number |
| Companion Flange Holding Tool |
T78P-4851-A |
| Companion Flange Remover |
T65L-4851-B |
| Pinion Bearing Cone Remover |
T71P-4621-B |
| Pinion Bearing Cone Replacer |
T71P-4621-C |
- Mark rear axle universal joint flange
in relation to the pinion shaft. Hold the rear axle universal joint flange
with Companion Flange Holding Tool T78P-4851-A and
remove the pinion nut. If a new differential ring gear and pinion (4209)
is being installed, the rear axle universal joint flange
need not be marked.


CAUTION: Never use a hammer to remove the rear axle universal joint flange
.
- Remove the rear axle universal joint flange with
Companion Flange Remover T65L-4851-B.

- With a soft-faced hammer, drive pinion out of differential pinion bearing (4621)
and remove through rear of rear axle housing
.
- To remove and install the differential pinion bearing (4630)
, use Pinion Bearing Cone Remover T71P-4621-B and Pinion
Bearing Cone Replacer T53T-4621-C.

- Measure the drive pinion bearing adjustment shims (4663)
, found under differential pinion bearing
, with a micrometer and record thickness.
Pinion Bearing Cup Removal
NOTE: Do not remove the rear axle pinion bearing cups (4628)
from the rear axle housing
unless the rear axle pinion bearing cups
are damaged.
- Tap alternately (with a brass drift of suitable length) on each side of the rear axle pinion bearing cups
during removal to prevent rear axle pinion bearing cups
from cocking in the carrier bore.
Differential Case Runout Check
SPECIAL SERVICE TOOL(S) REQUIRED
| Description |
Tool Number |
| Differential Side Bearing Replacer |
T57L-4221-A |
If the ring gear runout check (before disassembly) exceeds specification,
the condition may be caused by a warped ring gear, a damaged differential case
or loss of differential bearing preload. To determine
the cause of excessive runout, proceed as follows:
- With the pinion removed, place differential case/gear subassembly with differential bearings
and differential bearing cups
in rear axle housing
.

- Install a 6.75 mm (0.265-inch) differential bearing shim
on the LH side of subassembly.

- Install the LH bearing cap finger-tight.

- Install progressively larger differential bearing shims
on the RH side until the largest differential bearing shim
selected can be assembled with a slight drag feel.

- Install the RH side bearing cap. Install bearing cap bolts. Tighten both RH
and LH bolts to 95-115 Nm (70-85 lb-ft).
- Rotate the assembly to ensure free rotation.

- Install Dial Indicator with Bracketry TOOL-4201-C or equivalent. Check and
note ring gear runout.

- If the runout is within specification, the original out of specification
runout was caused by insufficient differential bearing preload. If runout
exceeds specification, proceed to step 9.
- Remove the differential case
from the rear axle housing
.

- After removing rear axle differential gear case bolts (4216)
, remove ring gear using a
drift that will bottom in ring gear bolt holes. Strike at alternate holes
around the gear.

- Install differential assembly, including differential bearing cups
and differential bearing shims
, in rear axle housing
.

- Tighten bearing cap bolts to 95-115 Nm (70-85 lb-ft) and
rotate assembly to ensure proper seating of differential bearing cups
.

- Check runout of differential case flange with a Dial Indicator with
Bracketry TOOL-4201-C or equivalent. If runout is within specification, 0.076mm
max. (0.003 inch), install a new differential ring gear and pinion
. If runout exceeds specification, ring gear is true and
trouble is due to either a damaged differential case
or differential bearing cups
and differential bearings
. Visually inspect bearings. If differential bearing cups
and differential bearings
are not damaged, replace both differential case
and differential bearing cups
and differential bearings
. Recheck runout with new parts
( differential case and differential bearing cups
/ differential bearings
).

NOTE: Press against the differential bearing cup
only.
- Press new differential bearings
on differential case hubs using Differential
Side Bearing Replacer T57L-4221-A1 and install differential assembly in rear axle housing
without ring gear.
- Check differential case
runout again with new differential bearings
and differential bearing cups
. If runout is now within limits, use new differential bearings
and differential bearing cups
for assembly. If runout is still excessive, differential case
is damaged and should be replaced.