Transmission slipping is when the engine transmission systems register errors in shifting.
In a manual car, the problem always stems from the clutch being faulty. For automatic cars, errors in transmission may arise from anywhere.
Here is an article about a slipping transmission in both manual and automatic transmissions.
How Do You Know That Your Transmission is Slipping?
A car with a transmission problem can register an RPM up to 3500. If this problem is not corrected, the constant high RPM can irreparably damage the transmission.
Acceleration delays are another sign of transmission slippage. Acceleration delays cause the engine to consume more fuel than it should. Not only does fuel efficiency decrease, but the performance of your car suffers as well.
If you have problems when reversing, a faulty transmission could be the cause. The car may a long time to engage the reverse gear, or may not engage it at all. If this problem is not corrected, the transmission will eventually be damaged.
There are cases where shifting gears produces a harsh noise or response. You may also notice that your car has an unusual odor or burning smell every time you shift gears. In other scenarios, the car may refuse to shift a gear and stall. All these are signs that your engine’s transmission is slipping.
Causes of a Slipping Transmission
There are several causes of transmission failure in a car. When troubleshooting your car engine, look out for any of the following problems.
1. Issues with Transmission Fluid
Problems with the transmission fluid easily lead to slipping of the transmission. One of these problems is low levels of transmission oil. When the fluid level drops, the pressure required to engage the gears is reduced. This causes a strain during shifting, which leads to overheating of the gearbox. A reduction in the transmission fluid level can be the result of fluid leaks in the engine.
Leaks may be due to cracked fluid lines or a perforated transmission oil pan. A worn gasket, faulty seals, or a crack in the torque converter will all cause fluid leakage. If you do not correct these problems, the leaking fluid may cause internal damage to your car engine.
Transmission slipping can also be caused by burning the transmission fluid. The burnt fluid smells like burnt toast and has an abnormally dark color. If the transmission fluid burns, it becomes ineffective. This only affects the ability to shift gears. There is no damage to your transmission system.
Transmission fluid burns if there are impurities in the fluid. Contaminants enter the fluid due to the wear of components in the transmission. You can detect both problems by checking the status of the fluid.
2. A Slipping Clutch (Manual)
Clutch problems are the main cause of transmission slip in vehicles with manual transmission. The vehicle clutches wear out and cause problems when shifting gears. If your manual car has more than 200,000 miles on the clock, it is time to inspect the clutch.
It is also possible that you will wear out your clutch due to overworking it. If you always keep your foot on the clutch even after shifting, it will wear out the clutch disc quickly. Another reason that causes clutch slippage is when transmission oil leaks onto the clutch.
Clutch problems may also occur if the clutch pressure plate is damaged. The pressure plate uses a high-tension spring which distributes the pressure over the entire clutch. If the pressure is uneven, your clutch will begin to fail.
In automatic vehicles, the clutch plate is located on the transmission and torque converter. When these clutch plates wear, this causes the transmission fluid to drip or burn.
3. A Faulty Input Shaft Seal
Sometimes a transmission failure is due to a leak in the axle seal. The leak spreads to the transmission and clutch discs. If the leak is not repaired in time, it can cause major problems to your engine.
4. Faulty Axle Seal
Transmission slippage can also be the result of a worn axle seal. In such cases, only the axle seal needs to be replaced.
Fixing Issues in Transmission Slipping
Fixing Transmission Fluid Problems
If the transmission fluid is low, you must top it up with the fluid intended for your vehicle. Switch on your car to warm up the transmission fluid. Always use transmission fluid that has been specially made for your vehicle. Using the wrong transmission fluid will destroy your transmission.
If the fluid is below the “Add” mark, you must top it up with the fluid specific to your vehicle. Use a funnel to top up the transmission fluid to the recommended level. After this repair, check again to see if this has solved the transmission slippage problem.
Examine the transmission fluid for dark particles and a burnt smell. Drain the transmission fluid and replace it with fresh fluid. Start your car to warm up the engine. Lift your car onto a jack stand and loosen the screws on the transmission pan. Place a container under the pan to collect the draining liquid.
Clean the transmission oil pan and the magnet before putting them back in place. You must also replace the filter. If the gasket is worn or aged, replace it before reattaching the transmission oil pan. Fill in the new transmission fluid using a funnel and check whether this solves the slipping problem.
Lift your car onto a jack stand and check where the leak is coming from. Determine if you can repair the leak yourself or if you need to take your car to a mechanic. Transmission leaks can be repaired at home with sealants bought at a car dealership.
Taking Care of Clutch Problems
The only way to determine if your clutch is slipping is to perform a manual test. On a car with a manual transmission, you can do this by trying to roll your car in third gear. Engage the car and shift the transmission to third gear. If the car stops immediately, your clutch is not the problem.
If your car starts to roll, then you have a faulty clutch. You should also catch the smell of something burning from the engine. This is because the engine speed is high and both the transmission oil and the clutch disc are overheated.
Worn out clutch discs will need replacing. This is best done by a professional mechanic.
Replacing Axle and Input Shaft Seals
A faulty input shaft means the entire transmission needs replacing. It is a complex task that needs a trained mechanic. Since you will be paying more for the job, you should get a mechanic who will give you a good deal.
Unlike the input shaft, the axle seal is easy and cheaper to replace. You only need to change the axle seal itself and your transmission will work fine.
Transmission slip is one of the most common problems faced by manual and automatic vehicles. If the cause of transmission slip is minor, you can solve it with some simple DIY tricks. If you are not sure how to solve bigger problems like replacing gaskets, take your car to a mechanic.