# Driveline

## Front Driveshaft and U-Joints

### REMOVAL & INSTALLATION

Front driveshaft exploded view

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The following procedure applies only to 4 x 4 vehicles.

1. Raise and safely support the vehicle securely on jackstands.
2. If equipped, remove 3 front driveshaft shield retaining nuts and remove the driveshaft shield.
3. Matchmark the driveshaft yoke and axle pinion flange.
4. Matchmark the driveshaft yoke and transfer case flange.
5. Remove the bolts retaining the yoke to the axle flange.
6. Separate the yoke from the flange. It may be necessary to pry it free with a small prybar.
7. Remove the bolts and disconnect the driveshaft from the transfer case. It may be necessary to pry it free with a small prybar.

To install:

8. Place the driveshaft to the transfer case flange and axle pinion flange noting the index marks made during removal. Tighten the bolts to 87 ft. lbs. (119 Nm).
9. If equipped, install the front driveshaft shield and 3 retaining nuts.
10. Road test the vehicle and check for proper operation.

### U-JOINT REPLACEMENT

#### Single Cardan Universal

Partially pressing the bearing from the center yoke

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Removing the bearing cup from the center yoke socket

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Removing the bearing from the rear of the center yoke

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1. Remove the driveshaft from the vehicle and place it in a vise, being careful not to damage it.
2. Remove the snaprings which retain the bearings in the flange and in the driveshaft.
3. Place U-Joint Tool T74P-4635-C or an equivalent joint press, onto the driveshaft.
4. Slowly tighten the tool to press the spider towards one side. When it will not move any further, remove the tool and pull the bearing cup out of the bore with pliers.
5. Remove the other bearing cup in the same manner and remove the spider assembly from the driveshaft. Discard the spider assemblies.

To install:

6. Clean the yoke bores with light sand paper being careful not to change the dimension of the bores.
7. Remove the bearing cups from the new universal joint. Make sure all the needle bearings are still in place and held against the sides of the bearing cups with grease.
8. Start a new bearing cup into place with the press. When the cup is firmly held in place but still below the inner edge of the bore, install the spider. Be careful not to push a needle bearing out of place.
9. Fit the bearing cup into the other side of the bore and begin pressing it into place. Press the cup a little at a time and keep checking to make sure the spider turns freely in both cups. When both cups are pressed fully against the spider, install the snaprings.

If the bearing cups will not press in far enough to install a snapring or if the spider stops moving freely, a needle bearing has fallen out of place in one of the bearing cups. Stop pressing and disassemble the universal joint to re-position the bearings. If assembly is forced, the needle bearings and cups will be destroyed.

10. Install the remaining joint in the same manner.
11. Install the driveshaft and grease the new universal joints.

## Rear Driveshaft and U-Joints

### REMOVAL & INSTALLATION

#### One-Piece Shaft

The bolts retaining the rear driveshaft yoke-to-differential flange require a 12mm, 12 point wrench or socket to loosen them

Remove the bolts retaining the rear driveshaft yoke-to-differential flange

Separate the driveshaft from the axle flange and ...

... disengage the driveshaft from the transmission output shaft

Insert a plug onto the splines of the transmission output shaft to prevent fluid from leaking out

1. Matchmark the driveshaft yoke and axle pinion flange.
2. Remove the bolts retaining the yoke to the axle flange.
3. Separate the yoke from the axle flange. It may be necessary to pry it free with a small prybar.
4. Slip the driveshaft off the transmission output shaft splines.

To install:

5. Lubricate the splines of the yoke with a suitable long life grease (Ford recommends a Teflon® based grease) and install to the transmission output shaft.
6. Connect the driveshaft to the rear axle ensuring the index marks made during removal are lined up.
7. Install the 4 retaining bolts and tighten to 87 ft. lbs. (119 Nm).
8. Road test the vehicle and check for proper operation.

#### Two-Piece Shaft

Two-piece driveshaft with a slip yoke at the transmission end

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1. Matchmark the driveshaft yoke and axle pinion flange.
2. Remove the bolts retaining the yoke to the axle flange.
3. Remove 2 center bearing support bolts.
4. Lower the driveshaft and slide the yoke off the transmission output shaft.

To install:

5. Lubricate the splines of the yoke with a suitable long life grease and install to the transmission output shaft.
6. Place the driveshaft in position and start the center bearing support bolts finger-tight.
7. Connect the driveshaft to the rear axle ensuring the index marks made during removal are lined up.
8. Install 4 retaining bolts and tighten to 87 ft. lbs. (119 Nm).
9. Tighten 2 center bearing support bolts to 39-53 ft. lbs. (53-72 Nm).
10. Road test the vehicle and check for proper operation.

### U-JOINT REPLACEMENT

#### Single Cardan Universal

Refer to the Single Cardan Universal procedure under the Front Driveshaft portion of this section.

#### Double Cardan Joint

Exploded view—double cardan universal joint

Click to enlarge

1. Working at the rear axle end of the shaft, mark the position of the spiders, the center yoke, and the centering socket yoke as related to the companion flange. The spiders must be assembled with the bosses in their original position to provide proper clearances.
2. Remove the snaprings which retain the bearings in the flange and in the driveshaft.
3. Place U-Joint Tool T74P-4635-C or an equivalent joint press, on the outer universal joint in the center yoke.
4. Slowly tighten the tool to press the spider towards one side. When the bearing cup protrudes about 3/8 inch from the bore, remove the tool, clamp the bearing cup in a vise and tap on the center yoke to drive it away from the cup.
5. Remove the opposite bearing cup in the same manner and remove the spider. Note the position of the lubrication fitting, if equipped.
6. Remove the centering socket yoke and press the other universal joint out in the same manner. Be careful not to distort the slinger ring on the driveshaft yoke.

To install:

7. Clean the yoke bores with light sand paper, being careful not to change the dimension of the bores.
8. Remove the bearing cups from the new universal joint. Ensure that all needle bearings are still in place and held against the sides of the bearing cups with grease.
9. Place the new spider into the driveshaft yoke. Make sure the lubrication fitting is in the original location so that it will be accessible with the driveshaft installed.
10. Fit the new bearing cups into place, then push them in with the press. Be careful not to push a needle bearing out of place. Keep checking to make sure the spider turns freely in both cups. When both cups are pressed fully against the spider, install the snaprings.

If the bearing cups will not press in far enough to install a snapring or if the spider stops moving freely, a needle bearing has fallen out of place in one of the bearing cups. Stop pressing and disassemble the universal joint to re-position the bearings. If assembly is forced, the needle bearings and cups will be destroyed.

11. Install the centering socket yoke and the remaining joints in the same manner.
12. Install the driveshaft and grease the new universal joints.

### DRIVESHAFT BALANCING

Marking the driveshaft

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Installing the hose clamps on the driveshaft

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Rotating the clamps

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Driveline vibration or shudder, felt mainly on acceleration, coasting or under engine braking, can be caused, among other things, by improper driveshaft installation or imbalance.

If the condition follows driveshaft replacement or installation after disconnection, try disconnecting the driveshaft at the axle and rotating it 180°. Then, reconnect it. If that doesn't work, try the following procedure:

1. Raise and support the truck on jackstands so that all wheels are off the ground and free to rotate. The truck must be as level as possible.
2. Remove the wheels. Install the lug nuts to retain the brake drums or rotors.
3. Start the engine, place the transmission in gear and increase engine speed to the point at which the vibration is most severe. Record this speedometer speed as a reference point.
4. Shift into Neutral and shut off the engine.
5. Check all driveshaft attachment fasteners, U-joint bearing caps, U-joint cap retaining rings or cap locating lugs. Tighten any loose fasteners, replace any missing, damaged or shaved retaining rings or lugs. If worn U-joints are suspected, replace them. If everything is normal, or if any corrections made do not solve the problem, continue.
6. Start the engine, place the transmission in gear and increase engine speed to an indicated road speed of 40-50 mph (64-80 km/h). Maintain this speed with some sort of accelerator control, such as a weight on the pedal, or have an assistant hold the pedal.

CAUTION
The following procedure can be dangerous! Be careful when approaching the spinning driveline parts!

7. Carefully raise a piece of chalk until it just barely touches the driveshaft at the front, middle and rear. At either end, try touching the shaft about an inch or so from the yokes. Don't touch any existing driveshaft balancing weights. The chalk marks will indicate the heavy points of the driveshaft. Shut off the engine.

It helps greatly to steady your hand on some sort of support.

8. Check the driveshaft end of the shaft first. If the chalk mark is continuous around the shaft proceed to the opposite end, then the middle. If the chalk mark is not continuous, install 2 screw-type hose clamps on the shaft so that their heads are 180° from the center of the chalk mark.
9. Start the engine and run it to the speed recorded previously. If the vibration persists, stop the engine and move the screw portions of the clamps 45° from each other. Try the run test again.

WARNING
Check the engine temperature!

10. If the vibration persists, move the screw portions of the clamps apart in small increments until the vibration disappears. If this doesn't cure the problem, proceed to the other end, then the middle, performing the operation all over again. If the problem persists, investigate other driveline components.

## Center Bearing

### REMOVAL & INSTALLATION

1. Remove 2 center bearing retaining bolts and remove the center bearing and driveshaft assembly.
2. Check the center bearing for wear or rough action by rotating the inner race while holding the outer race. If wear or roughness is evident, replace the center bearing assembly. Examine the rubber cushion for evidence of hardening, cracking, or deterioration. Replace as required.

To install:

3. Place the bearing in the rubber support and the rubber support in the universal shaped support, if removed.
4. Install the center bearing and drive shaft assembly. While supporting the center bearing in position, install 2 retaining bolts and tighten to 39-53 ft. lbs. (53-72 Nm).
5. Road test the vehicle and check for proper operation.