QuestionI have a 99 Ram 1500 Quad Cab 4x4. I recently noticed a puddle on my driveway, under the rear differential. I thought it was the cover gasket, but noticed that the oil has been sprayed all over the underside of the truck. That tells me it's more likely to be the pinion seal, rather than the cover gasket. Right? Anyway, I'm replacing both, to be on the safe side. Was wondering what details I need to know to change the pinion seal? What are the torque specs for the yoke nut, and the cover bolts?
AnswerPINION SEAL
REMOVAL
Raise and support the vehicle.
Scribe a mark on the universal joint, pinion yoke, and pinion shaft for reference.
Disconnect the propeller shaft from the pinion yoke. Secure the propeller shaft in an upright position to prevent damage to the rear universal joint.
Remove the wheel and tire assemblies.
Remove the brake drums to prevent any drag. The drag may cause a false bearing preload torque measurement.
Rotate the pinion yoke three or four times.
Measure the amount of torque necessary to rotate the pinion gear with a (in. lbs.) dial-type torque wrench. Record the torque reading for installation reference.
Hold the yoke with Wrench 6719. Remove the pinion shaft nut and washer.
Remove the yoke with Remover C-452 Yoke Removal
Remove the pinion shaft seal with suitable pry tool or slide-hammer mounted screw.
INSTALLATION
Clean the seal contact surface in the housing bore.
Examine the splines on the pinion shaft for burrs or wear. Remove any burrs and clean the shaft.
Inspect pinion yoke for cracks, worn splines and worn seal contact surface. Replace yoke if necessary
NOTE: The outer perimeter of the seal is pre-coated with a special sealant. An additional application of sealant is not required.
Apply a light coating of gear lubricant on the lip of pinion seal.
Install the new pinion shaft seal with Installer C-3860-A and Handle C-4171
NOTE: The seal is correctly installed when the seal flange contacts the face of the differential housing flange.
Position the pinion yoke on the end of the shaft with the reference marks aligned.
Seat yoke on pinion shaft with Installer C-3718 and Wrench 6719.
Remove the tools and install the pinion yoke washer. The convex side of the washer must face outward
CAUTION: Do not exceed the minimum tightening torque when installing the pinion yoke retaining nut at this point. Damage to collapsible spacer or bearings may result.
Hold pinion yoke with Yoke Holder 6719 and tighten shaft nut to 285 N·m (210 ft. lbs.) Tightening Pinion Shaft Nut Rotate pinion shaft several revolutions to ensure the bearing rollers are seated
Rotate the pinion shaft using an (in. lbs.) torque wrench. Rotating torque should be equal to the reading recorded during removal, plus an additional 0.56 N·m (5 in. lbs.) Check Pinion Rotation Torque
CAUTION: Never loosen pinion gear nut to decrease pinion gear bearing rotating torque and never exceed specified preload torque. If rotating torque is exceeded a new collapsible spacer must be installed. The torque sequence will then have to be repeated.
If the rotating torque is low, use Yoke Holder 6719 to hold the pinion yoke Tightening Pinion Shaft Nut and tighten the pinion shaft nut in 6.8 N·m (5 ft. lbs.) increments until proper rotating torque is achieved
NOTE: The bearing rotating torque should be constant during a complete revolution of the pinion. If the rotating torque varies, this indicates a binding condition.
The seal replacement is unacceptable if the final pinion nut torque is less than 285 N·m (210 ft. lbs.)
Install the propeller shaft with the installation reference marks aligned.
Tighten the universal joint yoke clamp screws to 19 N·m (14 ft. lbs.)
Install the brake drums.
Install wheel and tire assemblies and lower the vehicle.
Check the differential housing lubricant level.
