Can Bad Transmission Damage The Engine? What Are The Symptoms?


Although a bad transmission can “possibly” damage the engine there really isn’t anything that could do so.

Normally it’s the opposite way.

The engines are much tougher than the transmissions, and the transmissions usually fail well before the engine fails.

What are the symptoms of a bad transmission?

Gears Don’t Change:

Believe it or not, there are still many drivers in the world who prefer a manual transmission with a pedal and a gear lever.

Despite the simple design, the manual transmission can also cause problems.

One of the problems that You may encounter is that the transmission does not change gears when you press the pedal and move the shift lever.

This can happen when you try to turn on the first gear after stopping, or when you switch adjacent gears.

The usual cause of this problem may be low transmission fluid, wrong viscosity of the fluid, the need to adjust the cable drive gear or linkage.

Problems with the transmission can occur for various reasons, which we will also discuss.

Smell Of Burning:

If you feel that the transmission fluid smells burnt, then this clearly indicates a problem.

The smell of burning may indicate that the transmission is overheating.

Transmission fluid not only lubricates numerous moving parts of the box but also cools them.

Some cars even have a special small radiator (oil cooler) that removes heat from the box.

The smell of burning can be felt as a result of a low level of contamination of the transmission fluid, which indicates the presence of a leak or the need to replace the oil.

If you think that the transmission is protected from wear when it is in neutral gear, You will be surprised. 

Noise while in neutral gear:

Naturally, if you hear strange sounds when changing gears, something is wrong with the transmission.

But what if you hear strange sounds when the car is in neutral gear? Yes, this may indicate a problem with the transmission.

Often this fault can be solved simply and inexpensively, as well as many minor problems by simply replacing the transmission fluid.

It should be remembered that, as with engine oil, different cars require different transmission fluid, information about which can be found in the operating manual.

In turn, too much noise coming from the box in neutral gear may indicate a more serious problem, such as mechanical wear that requires replacement parts.

In this case, most likely, the worn intermediate reverse gear or worn bearings, as well as worn gear teeth, are to blame.

Losing control while driving is not the most fun adventure. Next, we will talk about such a problem as jumping off the transmission.

Gear Skipping:

If the transmission is working properly, the car will continue in the gear that You or the computer choose, depending on the engine speed, until you or the automatic transmission make the switch.

But it may happen that the transmission suddenly jumps off while driving, and (on the manual transmission) the lever will stand in the neutral position.

This is annoying at best, but at worst it can be dangerous: when you press the gas pedal to avoid losing control of the car, You will absolutely not like the fact that the transmission does not change gears.

Don’t risk it – if the transmission starts to slip,  you need to make a diagnosis of the box.

Clipping of the clutch:

This is another problem that haunts owners of cars with a manual transmission – clipping of the clutch. If the clutch is attached, the clutch disc does not detach from the flywheel when the pedal is pressed.

When you press the clutch pedal, it does not turn off, so the gears do not switch. The presence of a problem is indicated by a grating sound that the driver hears every time they try to change gear.

Fortunately, this problem is usually not very serious, and repairs will not be as expensive as fixing other transmission failures.

Most often, the cause is a weak clutch pedal.

If there is too much free travel, the cable or rod between the pedal and the clutch disc cannot detach the clutch disc from the flywheel (or clutch basket).

Some problems with the clutch are easy to notice even for a layman – if you know what to pay attention to. We will talk about the most obvious faults later.

Liquid leak:

Transmission fluid leakage is probably one of the most obvious signals that You need to pay attention to the gearbox.

Automatic transmission fluid is so important for shifting gears that even a small leak can cause serious problems.

If the gearbox is in good condition, the transmission fluid for automatic transmissions must be bright red, transparent and have a sweet smell.

When checking the transmission fluid of the automatic transmission, make sure that it is not darkened and does not have a burning smell.

Otherwise, you need to contact a mechanic to replace the fluid.

Unlike engine oil, transmission fluid should not be consumed over time, so if you notice that the fluid level has dropped, no doubt it is leaking.

If you have a manual transmission, it is not enough to simply open the hood and get the dipstick to check the liquid level.

In the manual transmission, the oil level is checked directly in the gearbox itself, usually through the filling hole.

If you think that the gearbox is leaking, contact your mechanic to identify and fix it.

If the oil level is sufficient, there are several other simple ways to find the fault, which we will discuss later.

Warning light ” Check engine”

If the “Check Engine” light comes on, it may be a warning that there are some problems in the gearbox/transmission.

The “Check Engine” lamp may indicate a lot of problems that are not related to the transmission but do not ignore this warning.

In new cars, sensors are installed throughout the engine that detects violations of its normal operation and informs the computer about malfunctions.

As for the transmission, these sensors can detect vibrations and problems at an early stage that You may not notice.

If you want to check whether the “Check engine” light indicates a transmission malfunction, you can purchase a diagnostic tool that connects to the driver’s side panel.

The diagnostic device displays the code corresponding to the fault of a specific component. If the displayed code indicates a problem with the checkpoint, it’s time to visit the mechanic.

But even if the “Check Engine” lamp is not lit, you can detect problems with the gearbox. Next, we will talk about how the transmission behaves in the presence of a malfunction.

Grinding or shaking

Depending on whether you drive a car with a manual or automatic transmission, transmission failures can manifest themselves in different ways.

As we said earlier, the failure of the manual transmission can most often be determined by the grinding sound when changing gears.

If you hear a screech when the clutch is fully squeezed out and you change gears, it may be time to change or adjust the clutch.

Or one of the synchronizers is simply worn out or damaged. There are various factors that can cause grinding when changing gears.

If there are problems with the automatic transmission,

You may feel the car suddenly shifts when switching, in contrast to the usual smooth and almost imperceptible transition to another gear, or you may hear a sharp unpleasant sound when switching.

Both of these signs indicate that you need to paycheck the gearbox. If there is no smoothness when switching, you need to contact a mechanic for maintenance or repair of the automatic box.

But there are other signs of transmission failure. Next, we will talk about what sounds you need to listen to.

Howling, humming, or buzzing sound:

It is quite difficult to tell exactly what sounds a faulty transmission makes, but You will understand that there is clearly something wrong with the gearbox if you hear strange sounds.

All cars have their own design features, so the sounds produced by the gearbox are also different, but if you have an automatic transmission, then you will most likely hear a howling, humming or even buzzing sound when a malfunction occurs.

A faulty manual transmission usually emits sharper mechanical sounds.

If you hear a clang when you change gears, then you definitely need to contact a professional.

A clanking sound does not always indicate a faulty transmission. The culprit may be a joint of equal angular speeds (CV joint) or even a differential.

At first, strange sounds will only occur occasionally, but if you ignore them, you will hear them more and more often.

The lack of response:

The transmission is designed in such a way as to constantly ensure correct gear shifting, so if the transmission does not turn on, it is a sign of malfunction.

If You have a car with a manual transmission, and you notice that after switching gears, the speed increases, but the car does not develop speed, then, in this case, the fault may be a worn clutch or a more serious transmission problem.

Automatic boxes may also have a problem with no response, but this is usually the case when selecting the “Park” or “Drive” selector position.

The box should quickly switch to any of these modes, but if it “thinks”, it is most likely due to a malfunction.

Can low engine oil cause transmission problems?

Although engine oil and transmission oil are two separate things,  The oil level should be checked once a day, preferably in the morning before the trip.

It should be remembered that a small amount of engine oil always burns even with a technically sound engine.

In the case of intense oil fumes, the causes should be found in mechanical failures of the engine and the quality of the oil (unsatisfactory oil characteristics).

How do you know if you blew your transmission?

When the car suddenly starts giving off vibrations and strange noises like grinding or whining, the transmission suggests, “Take me to a mechanic.”

You’ll also experience slipping gears – where the engine speeds up or down, but the vehicle doesn’t speed up very quickly or move at all (that’s a very bad sign).

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