How to Troubleshoot a Ring Pinion Problem on a Ford Expedition
- 1). Raise and support the vehicle on jack stands. Place a drip pan under the center section of the axle. Remove the 13 mm bolts from the rear axle cover with a 13 mm socket and ratchet.
- 2). Pull the rear axle cover off slowly to allow the oil to drain into the pan. Turn the cover so the inside of the cover is facing up. Examine the oil on the cover in the sunlight. Look for signs of metal shavings, which show up as glitter in the light.
- 3). Inspect the ring and pinion gear for unusual wear patterns. Inspect the quantity of oil that came out of the carrier. The carrier is the mechanism taking up the inside of the axle housing to which the ring and pinion gear are attached.
- 4). Grab the driveshaft and rock it back and forth as much as possible without moving the ring gear. If there is more than 10 to 15 degrees of rotation possible without moving the ring gear, the gears are worn and should be replaced.
- 5). Inspect the pinion gears for uneven wear and for the presence of the spacer between the gear and the carrier. If any problems are found, such as metal in the oil, uneven wear pattern on the gears or too much free play between the pinion and the ring gear, the carrier should be taken out and the gears replaced, or the entire unit should be replaced (depending on the extent of the damage).
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