Transmission slipping.

My transmission is slipping. I believe I have a leak somewhere.
Experienced mechanics share their insights in answering this question :
Hello. Fluid pressure is used inside the automatic transmission to convert the engines rotation into working torque. Any major leak inhibits operations, fluid pressure cannot build properly, and the transmission starts to slip as it cannot transfer the power. There is damage being done and it should be fixed immediately. Have a mechanic, like the ones here at YourMechanic, come out to inspect the leak and ensure an optimal transmission fluid level. A low level obviously indicates a leak. If the transmission is full, however, and the fluid is dark and burned, there may be an internal failure.

How to Identify and Fix Common car Problems ?

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If you don`t fix the leak and keep enough transmission fluid in your vehicle, it will lead to overheating. It could also lead to a lack of hydraulic pressure in your transmission, which will often cause your transmission to slip and struggle when it tries to engage and change from one gear to the next.
Low transmission fluid is one of the most common reasons for a slipping transmission. The most likely culprit is a problem in your system that`s causing the transmission fluid to leak.
Slipping gears are usually due to normal wear and tear, which causes them to not engage properly and to slip in and out of sync. It is rare, but there might be a malfunctioning set of gears in the transmission, which is usually due to bad original manufacturing.
In manual transmissions, slippage is frequently caused by a worn-out clutch. Replace the clutch, and often the problem goes away. For automatic transmissions, damaged or worn clutch plates, transmission bands, or solenoid packs are often the culprit and one or more of these need to be replaced.
If you have a leaking transmission, you might notice transmission performance problems because the fluid is low. These problems can include refusing to shift into gear or grinding between gears. The leaking fluid will drip more toward the center of your automobile; the transmission is not in the front.
To put it briefly, no you should never drive your vehicle if you believe there to be an issue with your transmission in any case. Once a transmission starts slipping it needs to immediately be repaired. Every time you drive it after you feel your transmission slip, it is a risk.
While not necessarily a sign of oncoming major transmission failure, slipping does indicate that your transmission is in serious need of service and repair. To leave it unchecked is to put both your vehicle and yourself, as well as other drivers and pedestrians, in danger.
When you accidentally use the wrong transmission fluid, there are a few common signs that your transmission will throw off indicating wrong fluid: The car will stall while shifting gears. Your engine will produce a clunking sound. The gears will begin to slip.
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.

LEAKING TRANSMISSION FLUID: WHY IT`S CAUSE FOR CONCERN

Left alone, the little leak will become a bigger one. Eventually, your transmission —which makes sure power gets from the engine to the wheels — won`t be able to perform as it should, and you may experience: Delayed engagement when placed in gear.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

my transmission is "slipping" 3% of the time
ANSWER : Hello. From what you describe, it would appear that your transmission is beginning to slip. This can be caused by many things. The first thing I would do is check the vehicle’s transmission. Automatic transmission use fluid pressure to operate, and will have all sorts of issues if the fluid is low or dirty. If the fluid checks out, I would then move on to looking at the transmission itself. It may be possible that one of the components, such as a sensor or solenoid may be going out and causing your issue. It may also be possible that the transmission is simply worn out and can no longer hold the engine torque, perhaps due to a worn clutch pack, valve body, or torque converter. In these cases of removal and overhaul of the transmission is required. You may be able to continue driving the vehicle, however, because it may cause the symptoms to worsen over time if the issue is not quickly addressed.

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My transmission is slipping. If I replaced it while that solve my problem? asked by Jose V on July 02, 2017 I have a automatic
ANSWER : Hi Jose: Thanks for your question. Below is some additional information in addition to that sent to you by John yesterday. Installing used parts, particularly a part as complex as a transmission, is not the best practice. If you have a transmission fault, the first thing to do is get the cause of the fault professionally diagnosed because some transmission faults are easy to fix, such as low fluid level, replacement of burnt fluid, or needed fixes on engine controls or wiring (transmissions are electronically controlled). YourMechanic offers that service as a transmission diagnostic and you can schedule that at your convenience.

After you know, for sure, what is wrong with the transmission then a decision can be made as to the most economic and effective repair strategy. That is, if the fix is not amongst the simple causes of transmission breakdowns, but rather is due to something like a worn out band, or a leaking clutch piston, then the transmission has to be removed, completely overhauled and re-installed, usually with a new torque converter. Without a diagnostic, even installing a new transmission may not resolve your issue if the fault lies in an engine control or electronic control component and this is why you need to first get the problem identified. Hope we can assist you with this.

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Transmission slips if I shut truck off and restart it will do fine for a few seconds then slip again
ANSWER : Hi there, thanks for writing in.

The reason is starts slipping at 30 is this is where it needs to change to second gear or third gear. The problem is most likely the servo piston for the second gear engagement is binding in the transmission housing due to a worn housing. The fix is to overhaul the transmission and have a sleeve put into the housing during the overhaul with an oversize servo kit. The only other fix would be to replace the transmission with a new or rebuilt unit. The reason it works after turning the car off and back on is because it sets a fault for itself and goes into limp mode, and turning it off will erase that fault until its seen again, at which point it will go into limp mode again. You can have this diagnosis verified by a qualified technician, such as one from YourMechanic, who can then provide you with a suggested repair plan.

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Transmission slips out of fifth gear, makes grinding sounds
ANSWER : This is possibly a transmission shifter adjustment issue (5th gear, non-engagement). The noise issue may be related, but it is potentially serious regardless. You don’t mention what kind of "transmission problems" caused you to have the clutch repaired, but that problem may be related as well. Regardless, you should have the slipping issue inspected by a professional, like one from YourMechanic, before driving it further.

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Can too much transmission fluid cause speedometer malfunctions?
ANSWER : Hi there. In most cases when you overfill the transmission fluid it can cause excessive foaming of the fluid or possible internal component failure due to excessive pressure inside the hydraulic lines. Sensors like the speed sensors however are rarely impacted by this situation. However, in regards to the possibility of probability of this; I would say perhaps a 10% chance.

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Why is my transmission slipping?
ANSWER : The transmission in your truck has the updated 4L60 series with a heavier duty forward gears and thrust bearings so your transmission problem is most likely the torque converter or front pump failure. The clutch materials in an automatic transmission are very thin and if you have had slipping for over 10k miles you may have caused even more internal damage to other internal components. You will most likely need to have the transmission replaced or overhauled with a new torque converter. All the lines will need to be flushed out also to keep from contaminating the new or rebuilt transmission. Replacing the transmission with a remanufactured or a good used transmission with a warranty would be the recommendation I would give, since the truck is under 10 years old and has low mileage. Have the transmission system thoroughly checked by a certified mechanic, such as one with YourMechanic, before condemning it and before any replacements or repairs are done.

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2013 Ford Focus Transmission Issue. Is it worth keeping the car?
ANSWER : Hi There,
This is a known issue in this generation Ford Focus and some Fiestas with the "Power Shift" transmission and there have been numerous recalls and lawsuits. Although, it is would be difficult to determine how much longer your transmission will last given the fact that you have many new parts, I would not recommend junking the car as it may still provide some valuable life left for you. I would recommend taking it to the dealer to see if these parts may be covered under the recall.

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My van transmission started slipping and the van is making a whining sound now. I had transmission fluid filled but it is even wor
ANSWER : It would be a good idea to check to be sure that the fluid level was not overfilled. Too much fluid creates shifting and operational problems just as too little fluid will. So, the level should be carefully verified. If the whirring noise is from the transmission (it could be wheel bearings for example), such noise could be from the torque converter, oil pump, or other rotating elements. The noise would have to be heard first hand by a mechanic to pin it down. If the transmission is not shifting properly, it could be as simple as a valve body issue (typically the valve body is replaceable on the vehicle) but there are also many other causes of shift difficulty such as broken or worn bands, failing clutch pistons and so forth. Some of these faults can be determined by using external gauges to measure internal hydraulic pressures within the transmission when you shift. Transmissions can be repaired; you won’t necessarily need a "new" transmission but yes, admittedly, such repairs can be costly. If you want to get a definitive diagnosis and get information about repair options, just request a transmission shift and noise diagnostic and the responding certified mechanic will help you with that. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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