The differential is one of the most important parts of the car. It ensures that the power is transferred from the engine to the wheels while compensating for the differences in speed of the driven wheels.
However, a defect can lead to huge problems. And unfortunately, an exchange is not an easy taskBut with a little craftsmanship and these instructions, you can do it.
What you need to consider before you start
Before you dare to exchange, you should be aware that it is a rather demanding repair which definitely requires a technical understanding. So if you are unsure, you should call in a professional. But with patience and the right tools, you can do the replacement yourself.
Preparation is the be-all and end-all
Before you start, you need to make sure everything is ready. A clean and well-lit work environment is the foundation for a successful repair. And of course the right equipment is a must:
- car jacks, jack stands
- wheel wrench or impact wrench
- socket wrench set, wrench, torque wrench
- brake cleaner, oil drip tray
- New seals, sealing compound, differential gear
- Safety glasses and gloves
Step 1: Jack up the vehicle
First, the vehicle must be placed on a level surface and the handbrake must be applied. Safety comes first – make sure the jack and jack stands are stable. Then remove the wheels to gain access to the differential.
Step 2: Drain the transmission oil
Now place a drip tray under the differential and open the drain plug. The old oil will drain out and as soon as everything is out, close the plug again. Make sure that the oil disposed of in an environmentally friendly manner is.
Step 3: Remove the old differential
Now comes the exciting part: The old differential has to go. Remove the drive shafts and loosen the bolts securing the differential to the axle housing. They can be very tight, so be prepared to torque wrench or even one rubber hammer to use. A little penetrating oil can't hurt either. Once you have loosened everything, you can carefully remove the differential from the axle housing.
Step 4: Cleaning and inspection
Before installing the new differential, the axle housing thoroughly cleaned Use brake cleaner and make sure to remove any old seal residue. Check the case also for damage or wear to avoid unpleasant surprises.
Step 5: Install new differential
Now you set the new differential and make sure that it seated correctly. Tighten the mounting bolts to the torque specified in the workshop manual. Now all that remains is to reconnect the drive shafts and tighten the bolts.
Step 6: Replace seals and refill oil
All damaged Seals are replaced, and you insert the new ones with some sealant to To avoid leaksNow you can fill in fresh transmission oil – make sure to use the amount and type of oil recommended by the manufacturer.
Step 7: Completion and test drive
After you have remounted the wheels and lowered the car, the last step is to test drive. You should pay attention to whether unusual noises or vibrations If everything goes well, you've made it!
Important tips for success
- safety equipment: Wear protective goggles and gloves to avoid injury.
- Keep the workshop manual handy: It contains important torque values and specific instructions. Alternatively, search for help in forums.
- Always pay attention to torque: All screws must be tightened to the correct torque to ensure a secure connection.
- Dispose of used oil in an environmentally friendly manner: Many workshops or recycling centers accept used oil.
Conclusion: Replacing the differential gear is possible!
With our Instructions and the right tools, you can replace your differential yourself and get your car back in shape. It takes a lot of time and patience, but in the end you save yourself the cost of expensive workshop work. Good luck with your project!
FAQ: Differential gear and transmission oil
1. How do I know if my differential gear is defective?
- Signs of a broken differential are loud noises (grinding, howling or clattering) while driving, especially when cornering. Vibrations or uneven driving behavior are also abnormalities.
2. How often should the Gearbox oil changed be?
- The Change interval for transmission oil varies depending on the vehicle and manufacturer. As a rule, a change every 60.000 to 100.000 kilometers is recommended.
3. Can I Change the transmission oil yourself?
- Yes, changing the transmission oil can be done by yourself with the right tools and some technical know-how. However, it is important to know the exact amount of oil and the correct oil type.
4. What happens if the wrong transmission oil is used?
- Using the wrong transmission fluid can result in inadequate lubrication, causing wear and damage to the transmission or differential.
5. Can I mix additives into my differential oil?
- There are special additives for gear oils that are designed to reduce friction or prevent leaks, for example. However, before using the additive, you should check whether it is suitable for the vehicle and the oil.
6. What does the viscosity information on the gear oil mean (e.g. 75W-90)?
- The viscosity class describes how thick the oil is at different temperatures. The number before the "W" indicates the cold viscosity (eg 75W for winter), the number after the hyphen indicates the viscosity at operating temperature (eg 90).
7. What is the difference between GL-4 and GL-5 oils?
- GL-4 oils provide less protection against high pressure loads and are suitable for manual transmissions and light axles. GL-5 oils have a higher proportion of EP (extreme pressure) additives and are intended for heavily loaded differentials and axles.
8. Is a differential gear the same in all vehicles?
- No, the differential can be constructed differently depending on the type of vehicle and drive system. Cars with rear-wheel drive, front-wheel drive or all-wheel drive have different types of differentials, such as open differentials or limited-slip differentials.
9. What is a limited-slip differential and when is it needed?
- A limited-slip differential ensures that both wheels on an axle receive more or less the same amount of power, even if one of them spins. It is mainly installed in sports cars and off-road vehicles to improve traction in difficult situations.
10. How much does it cost to have the differential replaced by a workshop?
- The cost of replacing the differential can vary greatly depending on the vehicle and the amount of work involved. As a general rule, you should expect costs between 500 and 5.500 euros.
What oils are available for the differential?
There are different types of transmission oil (also called differential oil) that are used depending on the vehicle type and the manufacturer's requirements. The following is an overview of the common types of transmission oil:
- Mineral gear oil:
- Based on refined petroleum
- Affordable and suitable for older vehicles
- Less heat resistant than synthetic oils
- Synthetic gear oil:
- Synthetically produced base oils
- Higher heat resistance and longer durability
- Better lubrication performance at extreme temperatures
- For modern vehicles and high-performance applications
- semi-synthetic gear oil:
- mixture of synthetic and mineral components
- Good compromise between cost and performance
- Suitable for many vehicles
- hypoid gear oil:
- Specially designed for hypoid gears used in differentials of modern vehicles
- High pressure resistance and extreme resilience
- Mostly used in rear-wheel drive cars
- ATF (Automatic Transmission Fluid):
- Especially for automatic transmissions
- Also suitable for some differentials, especially in vehicles with four-wheel drive
- Heat-resistant and optimized for hydraulic functions
- GL-4 gear oil:
- Suitable for manual transmissions and axles that have less high pressure loads
- Mostly used in passenger car manual transmissions
- Good protection against corrosion and wear
- GL-5 gear oil:
- For heavily loaded differentials and axles
- Higher pressure resistance than GL-4
- Often used in heavily loaded differentials
- LS oil (Limited Slip):
- Especially for vehicles with locking differentials (limited-slip differentials)
- Contains special additives that prevent the wheel from spinning and ensure a more even distribution of force
- single-grade gear oils:
- Oils with a fixed viscosity that work in a specific temperature range
- Outdated, rarely used
- multigrade gear oils:
- Oils that remain stable over a wide temperature range
- Modern vehicles almost exclusively use multigrade oils
It is important to use the oil recommended by the manufacturer to achieve optimum differential performance. The viscosity grade and API standard (eg GL-4, GL-5) are crucial points.