How do I know if I have a bad pinion bearing?

Asked By: Sumaia Eisenstein | Last Updated: 30th January, 2020
Category: automotive auto parts
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Regular clunking every few feet can also be an indicator of a broken pinion gear and/or chipped and damaged ring gear. Overly worn out bearings tend to make a howling noise when they do not properly support the gears. Rumbling while turning, on the other hand, is a sign of bad wheel bearings.

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Then, what happens if a pinion bearing breaks?

Only real problem is the pinion shaft retaining "bolt", if it's broken, you can't easily get the carrier out. Still, even if it was broken, it would take you all of 5 minutes to figure that out, and put it back together.

Secondly, what does a bad wheel bearing sound like? The most common symptom with a bad wheel bearing is a loud noise coming from the tire or wheel of the vehicle. It will sound like metal grinding on metal and will get louder as the vehicle goes faster. A bad wheel bearing can lead to uneven tire wear, which means you will have to purchase tires sooner.

In this manner, how long do pinion bearings last?

Under normal use and maintenance, pinion bearings can last a very long time. My 84 Suburban, which spent most of its life towing, just had a rear pinion bearing go bad at 187K miles.

How do you know if you have a bad differential?

Whining Differential or Transmission One of the symptoms most commonly associated with bad or failing differential or gear oil is a noisy transmission or differential. If the gear oil runs low or becomes excessively dirty, it can cause the gears to whine or howl as they turn.

29 Related Question Answers Found

What does a failing differential sound like?

A failing differential will often produce loud whirring noises or sometimes rattling. Any time you hear a strange noise coming from your vehicle, you should get it checked out by an auto repair expert. It can be any number of problems, including the differential.

How much does it cost to replace a rear pinion bearing?

Combined with the few hours of labor required for their replacement, the typical rear differential cost of repair is between $200 and $400. If gears are required, that number jumps a bunch. Rear differential repairs that include a new gear set may be $1,500 or even higher between parts and the labor to replace them.

What causes a pinion seal to go bad?

There are two problems to consider with a pinion seal leak. However, it is fairly common as well for the failure to be caused by too much runout of the pinion, caused by either incorrect preload on the pinion, or failure of the pinion bearing, the former often being caused by the latter.

What does a bad driveshaft sound like?

Abnormal Noises
This may result in unusual rattling, clunking, scraping, or even squeaking sounds from underneath the vehicle. U-joint in need of lubrication may also cause a squeaking noise at low speeds. Clicking or knocking sounds specifically can signify a faulty CV joint.

How do you know when your rear end is going out?


Signs of a Bad Rear Differential
  1. Noise in Gear from an Idle. When the vehicle is turned on and first put into drive, there may be a rattle or clanking noise coming from the rear of the vehicle.
  2. Grinding Gears at Speed. When the vehicle accelerates, there may be more noises like a hum or continued clank from the rear.
  3. Vibration and Fluid Leak.

What sound does a bad U Joint make?

Symptoms of a bad U-joint
Clunking noise when shifting into drive or reverse: By far the most common symptom of a bad U-joint is a loud clunking or banging noise when you put your car into gear.

How do you fix a loose pinion bearing preload?

Use an inch-pound torque wrench to check the preload. If the preload is too loose then remove shims so that the bearings will be tighter against the races and increase the preload. If the preload is too tight then remove the pinion gear and add shims so that the bearings will not be as tight against the races.

What is the proper pinion angle?

According to Currie, the average car crafter should strive for between 1 and 3 degrees between the tailshaft of the transmission and driveshaft, and 1 to 3 degrees between the driveshaft and pinion. Furthermore, the two angles should be nearly equal (between 1 and 3 degrees), but always opposite (see crude diagram).

What happens if you run out of differential fluid?

lack of oil in the differential will screw up the gears to a point where they'll be needed to be changed causing you the financial damage apart from having the other issues of a broken down car. In some cases it might even cause your car to be immovable (the rear axles won't turn).

How do you check differential fluid?


Check Fluid Level. Fluid should be at or just below the bottom of the Fill Plug hole. Fluid should not be black or gritty. If fluid is low, check for leaks.

Can you drive with a pinion seal leak?

The purpose of the axle seal is to keep transmission fluid from leaking. Depending on the size of the leak, it may be okay to drive with a leaking axle seal, but not for very long. If the leaking axle seal does not get fixed soon and the transmission is slipping, you could cause permanent damage to the transmission.

How do you replace a pinion seal?

How to Replace a Pinion Seal
  1. Materials Needed.
  2. Step 1: Chock the front wheels. It is recommended to lift your vehicle on flat ground.
  3. Step 2: Raise the axle.
  4. Step 3: Set the jack stands.
  5. Step 1: Set the parking brake.
  6. Step 2: Secure the driveline.
  7. Step 3: Remove the driveline mounting bolts.
  8. Step 4: Separate the driveline.

What causes rear differential damage?

The first and most common is loss of differential oil which can cause gears inside the differential housing to break, grind, or even block the rear wheels. Also, it is known that differentials can break if the inside gears are made of softer-type steel which is not able to withstand engine power and torque.

Where is the pinion seal located?

The pinion seal is located inside differentials of vehicles. The pinion seal is located near the pinion shaft and is designed so that fluid does not leak out of the differential.

How much does it cost to change rear differential fluid?


The average cost for a differential fluid replacement - rear is between $84 and $139. Labor costs are estimated between $52 and $67 while parts are priced between $32 and $72. Estimate does not include taxes and fees.

How long can I drive on bad wheel bearings?

The heat would crash the wheel completely. To avoid this situation, it is recommended to drive at the slower speed so that your wheel stays in action a few more hours. SO, while thinking how long can you drive on a bad bearing? You should not go more than 1000 miles as it might result in some bigger issue.

What happens if your wheel bearing goes out while driving?

It may become more pronounced during turns as the car's weight shifts and a different load is placed on the wheel. Ultimate damage: If you don't replace a damaged wheel bearing before it fails completely, the wheel will completely seize up. If this happens while you're driving, the results can be catastrophic.