Why is my transmission fluid leaking?
Recently my car has been losing transmission fluid. The leak is not external since there is never a puddle underneath the car from the pan, the back, or by the motor. My question is, where all can I check for external leaks before i force myself to drop the transmission or take it to a shop. The fluid is brown but not burnt smelling but it's losing half a quart of fluid a week. I would really appreciate some help.
My car has 139000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Generally, there are only a few places for leaking transmission fluid to go to since it does not burn off inside the transmission, unlike motor oil inside an engine. You have already ruled out the possibility of an external leak somewhere because of the lack of any visible signs of leaking.
A ruptured modulator can allow the fluid to be sucked into the engine (this is uncommon), or the fluid may have leaked into the transmission cooler. Another possibility may be a leak that is only active when the vehicle is in use or during times where hydraulic pressure is present in the transmission, such as while driving.
Try looking underneath the car and clean the surface areas under the transmission with a brake cleaner to get rid of any grease or oil spots. After cleaning, take the car for a drive. When you return, look underneath the car to see if you can spot any visible signs of fresh fluid leaking from under the transmission.
It is recommended that you get a certified technician, such as one from YourMechanic, to come to your location and determine the cause of the transmission leak.
How to Identify and Fix Common car Problems ?
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There could be a bad connection or a hole/crack in one of the transmission lines that is causing the leak. The transmission system has valves and solenoids that keep the flow of the fluid controlled when the vehicle is running. A damaged part or faulty valve/solenoid can result in a transmission fluid leak.
Faulty Transmission Pan or Gasket The fuel pan gasket is the number one culprit if your vehicle`s transmission fluid leaks when your car is parked. Cars with automatic transmissions have a pan gasket designed to catch most fluids leaking from the engine.
In many cases, leaking transmission fluid is simply a worn transmission pan gasket. This is the seal between the transmission pan (which is the reservoir for the transmission fluid) and the main transmission housing. The gasket will wear out over time and can start to leak.
Take a look beneath your car, or on the ground where you typically park. Transmission fluid will leave dark spots on your driveway or garage. If you notice spots on the ground, check all of your fluid levels to make sure everything looks good.
Causes of Transmission Fluid Leaks
This cause is easy to fix. All you`ll need to do is purchase a new gasket (which is relatively inexpensive). Also, make sure the bolts in the pan are tightened enough. If they`re not, this could result in a leak.
A transmission leak will not get better on its own. If it goes unchecked, vehicle operation will eventually be affected, and you may find yourself with an expensive repair. So, while it may be safe to drive with a leaking transmission, it`s not advisable, and you shouldn`t put off fixing the problem.
Generally, your car will not drive at all if you have completely run out of transmission fluid. This is especially true if your car uses an automatic transmission. In an automatic vehicle, the transmission fluid provides a coupling between the engine`s output and the gears in your transmission.
When the torque converter starts malfunctioning, you may feel shuddering and even slipping in overdrive. You usually notice your car shuddering because it feels like it`s vibrating. Your car will vibrate even when you`re not going very fast. The shuddering makes the car lag and is very noticeable.
Transmission fluid leaks will usually be reddish brown in color with a thin viscosity (new fluid) or brown with a thicker viscosity (old fluid). These leaks will typically be found near your car`s middle section.
How Much do Transmission Leaks Cost to Repair? The cost to fix a transmission fluid leak in a vehicle can be as little as $150 to replace a seal and around $1,000 to for a new torque converter.
A transmission leak will not get better on its own. If it goes unchecked, vehicle operation will eventually be affected, and you may find yourself with an expensive repair. So, while it may be safe to drive with a leaking transmission, it`s not advisable, and you shouldn`t put off fixing the problem.
While it is not especially dangerous to continue driving with a leaking transmission fluid, it can cause catastrophic damage to your engine. As soon as you notice your car is leaking transmission fluid, you should seek to contact a certified mechanic to have your transmission fluid serviced.
While it is not especially dangerous to continue driving with a leaking transmission fluid, it can cause catastrophic damage to your engine. As soon as you notice your car is leaking transmission fluid, you should seek to contact a certified mechanic to have your transmission fluid serviced.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
There is automatic transmission fluid in a manual transmission. Is it okay to leave or do I need manual transmission fluid?
ANSWER : This would depend on what the manufacturer recommends. Many manual transmissions do take automatic transmission fluid. If your transmission has ATF in it, it is very likely that it is supposed to have that in there. If not, it is likely that the transmission would not function properly with the wrong fluid. Many manual transmissions will also take engine oil as a lubricant. The best way to know for sure is to check your owner’s manual or call your local General Motors dealership to inquire.
My car is leaking transmission fluid – I can’t diagnose the leak
ANSWER : Based on the NHTSA database covering consumer complaints, as well as government mandated recalls and factory service bulletins, for your specific year, make and model, I do not see evidence of widespread complaints about transmission fluid leaks. Such leaks are, in fact, common in transmissions made by any car company, particularly if the transmission is older than say 10 years. There is a manual shaft seal, oil pan gasket, output shaft seals, case seals, torque converter seal (inaccessible) and so forth all of which are potential leak points on your transmission.
If you want to identify and resolve these leaks, certainly a certified Mechanic from YourMechanic could come out and perform a transmission leak inspection and let you know where the leak points are and what it will cost to resolve them.
Transmission fluid leaked while pulling a car out of mud
ANSWER : From the description you’re giving me, I’m not sure. I know many Fords, including my F150, have a circular seal type bell housing inspection cover near the transmission. Fluid pooled in this area generally indicates an engine oil leak from the rear main seal or a transmission leak from the front pump seal. The only way to know for sure is to have your truck’s transmission leak inspected firsthand by a professional. The team at YourMechanic is an excellent option since we make house calls.
New cars don’t have transmission fluid dipsticks Transmission fluid changing
ANSWER : That’s a very good question. The reason they have gone with no dipsticks is because they don’t want people messing with transmissions other there at the dealership. Some cars went through that a couple of decades ago. They make it a very involved, convoluted process all through, in order to change the fluid on these modern cars. They have special adapters you have to put. Some of them have to have scan computers in order to read the data and what’s in there, and then be able to change it. A lot of these companies claim that this new fluid is the "lifetime" fluid.
Most new use synthetic fluid can last a long time but any fluid is going to get dirty and wear out over time. I would change it at least every 80,000 – 100,000 miles but if you’ve got one that is really hard to change, you are better off hiring a mechanic to do it.
On some of the cars, it would be too hard for the do-it-yourself because of all that equipment you need. The professional mechanics already have that. Just call any good mechanic, like one from YourMechanic, and they will be able to perform a transmission fluid service for you.
1998 mercedes benz c280 transmission fluid leak from top
ANSWER : Hi there. Unfortunately, we are not able to receive pictures or video to pinpoint damage or identify parts for vehicles through this platform. The best way to identify this item is to search online for a detailed schematic of your C280 Mercedes-Benz or contact a local MB specialist mechanic or the dealership service department to determine the parts name and function. You might also want to have a MB specialist mechanic install and inspect your vehicle for further transmission fluid leaks to ensure the repairs are correctly completed.
Will adding Transmission Fluid with Stop Leak to a transmission with over 230,000 miles hurt it?
ANSWER : Both of these additives are designed to block small leaks or seepage from a gasket or rubber seal an not to fix major leaks or leaks where there will be excessive pressures, such as coolant leaks into the combustion chamber of the cooling system or leaks in high pressure areas of the transmission.
I would not recommend the use of these products unless a manufacturer specified to use them, like how GM did on their earlier models of the modular motors that had coolant leaking through the pores of the engine block from defective castings.
Before adding any of these additives I would recommend having a mechanic check the transmission fluid leak to see what the proper repair should be. These additives can sometimes clog systems and make matters worse in the long run.
Can I use alternative Transmission fluid to the quotes recommended fluid if i’m bringing my own parts?
ANSWER : I would recommend buying the correct fluid. The reason is because I want to make sure your car is taken care of and is running as long as possible. You wouldn’t want to put something foreign in your car that it may not accept unless you’re willing to accept risks. Different fluids have different chemicals in it. It may cost more right now, but you won’t have to spend money buying a new transmission or having one rebuilt.
Why is my transmission fluid leaking?
ANSWER : Generally, there are only a few places for leaking transmission fluid to go to since it does not burn off inside the transmission, unlike motor oil inside an engine. You have already ruled out the possibility of an external leak somewhere because of the lack of any visible signs of leaking.
A ruptured modulator can allow the fluid to be sucked into the engine (this is uncommon), or the fluid may have leaked into the transmission cooler. Another possibility may be a leak that is only active when the vehicle is in use or during times where hydraulic pressure is present in the transmission, such as while driving.
Try looking underneath the car and clean the surface areas under the transmission with a brake cleaner to get rid of any grease or oil spots. After cleaning, take the car for a drive. When you return, look underneath the car to see if you can spot any visible signs of fresh fluid leaking from under the transmission.
It is recommended that you get a certified technician, such as one from YourMechanic, to come to your location and determine the cause of the transmission leak.
