Knowing the symptoms of a bad rear differential will save you from a ton of drivability issues. A differential is that essential component that aids in the handling of your wheel system.
Differentials are what transfers all the power from the Vehicle transmission and engine to those individual wheels! No longer do both just turn at the same rate, a differential gives you that added bit of control you need with your vehicle.
If you start hearing weird noises coming from the wheels, or start feeling strange vibrations, go get checked out. They are most likely signs of a bad differential. Driving like that with a bad front differential will most likely = accident.
Rear wheel drives have a rear differential. Front-wheel drives have a front differential or transaxle that perform the same function as differntials. AWD and 4WD all have front and rear differentials.
Regardless of what kind you have make sure you have a good working effective differential. So If you have ever found yourself wondering what are the signs of a bad rear differential just relax and check-out this 5 minutes read.
Symptoms of a bad rear differential
Like every other mechanical component, a failing or bad rear differential will develop some symptoms to let the driver know there is a problem. In this article, we will go over some signs of a differential going bad.
#1 Excessive noise.
A failing differential [both front and rear] will make a whirring noise, whining noise, howling noise, and humming noise. These noises will change gradually when accelerating, decelerating, or turning a corner.
If the vehicle is humming or whirring, it probably has a damaged bearing in the axle or carrier or the bearing is worn. If it is whining or howling it is usually a ring and pinion gear failure.
A ring and pinion gear is most often worn, out of adjustment, or scored when this failure happens.
Simply put, if there is too much clearance (backlash) between the ring and pinion, there will be a clunking noise when shifting from park to drive. You can use a telescope to determine if it is a differential or rear axle problem.
Also, when the differential requires acclimatizing, for example, your axle itself obviously requires service and an inspection (for damage that a bad rear axle bearing can cause). Excessive noise is a common symptom of a bad rear axle shaft.
#2. Differential Failure Due To Lack of Lubrication.
Start by looking for leaks around the rear differential gasket. Then check to see if the rear axle leaks around the pinion gear seals.
Sometimes the leak is so substantial you will find dirt and oil collect right below the carrier and pinion gear, and down around the brake system areas.
#3. The Differential Is Overheated.
This can stem from using the wrong type of oil, no lubrication at all, worn gears, too much preload on bearings, too much backlash between the ring and the pinion.
Another cause is overload if you are hauling a heavy trailer or if you have loaded your equipment too heavily. Differential overheating is an indication of a low differential fluid supply.
#4. Hard To Handle the Wheels.
Suppose you are having trouble handling your wheels (especially in a corner). You may be forced to the side of the road to have the differential checked out along with other items connected such as the propeller and the universal bearing.
What about keeping your car on the roadway should the differential be worn out?
#5. Vibration.
Any unusual vibration in your car should be of concern. It may be a symptom of a rear-end differential, or other mechanical trouble from the rear wheels.
Whenever you sense a vibration from your rear wheels, quickly check out your differential or have it checked by your mechanic.
What causes a differential to go bad?
Since the differential is a simple mechanical device and not a complex one, few symptoms that can occur to make it fail. Let’s check them out.
#1. Lack of Oil.
A common cause for a bad differential, which could either lead to grinding at high speed, cause the carrier too break, or in most cases, block the rear wheels. Low differential fluid or lack of oil can happen due to several reasons.
It most often happens due to a worn-out differential seal, or a cracked housing which could cause oil leaks.
#2. Wrong oil type.
Another reason for a differential to be bad, is using the wrong type oil. You might notice an oil puddle under your vehicle, or oil spots on the differential housing, because the wrong oil type can cause leaks.
Or you may perceive a burning smell while driving. If the oil is not working as it should, it will not lubricate the differential, spider gears, and ring and pinion gears ver well. Once this happens, that will lead to friction, causing the differential and ring and pinion to fail.
Wrong oil type examples: Automatic transmission fluid (ATF)- Engine oil. There are oils made specifically for differentials and manual gears. If you do not know the right oil type to be using, consult your owner’s booklet.
#3. Normal wears.
Normal wear can cause it to fail. Well, what is normal wear? It is the normal deterioration which naturally occurs on mechanical components caused by using it frequently or regularly over time.
You should not mix normal wear with one that has got bad due to poor maintenance and services, lack of lubricating, or wrong oil type use. Normal wear happens because you have been using your vehicle.
#4. Reckless driving.
Finally, differential failure can be due to negligence, meaning you have pushed it very hard, gone dragging it several times, burnouts and everything. Also, it can go bad if it is made of light steel that cannot withstand the vehicle power and torque for much long.
Important Tips and Tricks for a long-life rear differential
You’ve got that cleared up and out of the way, and hopefully, that mind-numbing question, how do you know when your rear differential is bad, have you got? Here are the tips and tricks to prolong your rear differential.
Scheduled oil change
First and most important tip and trick to prolonging your differential lifespan is a regularly scheduled differential fluid change. The differential fluid is much thicker compared to engine oil, and the oil change intervals should be between 30k to 60k miles.
Recommended Oil
And of course, during servicing, make sure that you have the recommended oil. Using the wrong oil type is as bad as not changing it at all and can even do more harm.
Drive safely
Since the differential is located under the vehicle drive safely especially on a bad road, you don’t want to be rudely surprised by hitting it right on the rock. Hitting rocks can break the differential housing and result in leaks.
FAQs.
Q: What happens when your rear differential goes out?
Most of the time once the differential has gone out or the bearing has gone out you will start to hear some awfully strange noises. It is quite common for you to hear noises like a whirring, whining, growling, or howling noise.
This sound will significantly or less noticeably as you then accelerate or decelerate the vehicle. Sometimes you’ll find you can’t even hear the noise when you step on the throttle panel.
Plus, you may be having vibration problems with the way the vehicle handles. You may have a differential that is getting dangerously hot and burning in particular situations.
Q: What noise does a bad rear differential make?
The bad rear that is bad will develop a few strange sounds. We’re talking about some whirring noise, some humming noise, growling noise, whining noise.
But in many instances the noise the listener may hear would be the whining or howling noise indicating a damaged or worn-out ring and pinion gear.
Q: Can you drive with a broken rear differential?
You can drive your set of wheels with the bad rear differential but it can wreak havoc. The problem may come to pass that you are left in the middle of nowhere.
And in case you are wanting to know if you can drive with the totally unserviceable, broken differential, why no, don’t attempt it if you cherish saying yes to a mechanic every other day!
Q: How often should you flush your differential?
Automakers different replacement and service intervals for different components and differential flush is no exception.
However, most automakers recommend differential flush every 30,000 miles to 60,000 miles. It is a dirty job that requires to be undertaken by competent hands
Q: How long do differentials last?
Different distances based on driving habits, the level of maintenance, oil used while servicing, and many more. In normal use, and with good levels of maintenance, differentials should last 150000 miles or the life of a car.
Q: Can a bad differential cause a transmission problem?
A differential only has one important function; to transfer power from your vehicle transmission and engine to individual wheels.
With the differential, the driver can make good use of the optimum way to handle and control the vehicle, allowing him/her to have more precise control over your wheels instead of the wheels to be turning at the same rate.
Final Thoughts
It’s not just knowing the symptoms of a bad rear differential but also knowing bad pinion-bearing symptoms, and figuring the problem out on time. Meantime, besides figuring out the fault, the next thing is to call your mechanic for proper diagnosis and fix.
At this level, I’m pretty sure this content has exposed the signs of a failing differential, its causes, how to prevent it from happening, and tips and tricks of prolonging a differential life.