5 Symptoms of Overfilled Transmission and How to Correct

Jerry Wilson
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Consequences of Overfilling Your Transmission

One can’t avoid transmission fluid leakages. Transmission fluid is used for the smooth shifting of gears, reducing the risk of transmission failure. The severity of transmission fluid leakages vary depending on how much fluid was lost, and the length of time it was left unattended.

Here are some of the symptoms that indicate you have transmission fluid leakages in your automobile:

There’s sticky fluid on your car’s transmission.

There’s a burning smell from the car’s transmission.

Your automobile’s transmission is making strange sounds.

Your automobile’s transmission is emitting black smoke.

Your automobile doesn’t shift gears like it used to.

If your transmission fluid levels are low, they need to be replenished immediately so as to avoid excess strain on the transmission system. If the transmission fluid levels are too high, this leads to a transmission system failure due to overfilled transmission fluid.

Overfilled Transmission Symptoms

If your transmission is oversaturated with fluid, your vehicle may suffer from a number of problems that are related to that.

The transmission could experience an electrical failure which will cause the vehicle to stall.

The transmission fluid pump could seize up, causing the car to vibrate a great deal and not shift right.

When overfilled, a car’s transmission will not lubricate the gears and the differential appropriately. This means that they will lose their ability to spin freely, a condition called “hard shifting.”

An overfilled transmission may also have a coolant leak from a faulty transmission pump gasket.

Another issue related to an oversaturated transmission occurs when the transmission fluid has a high level of debris. The debris may lead to a transmission eruption.

So how do you correct this?

The simplest way is to take your car to a transmission service shop and have them dispose of the fluid. A quality transmission service should go through the following process to drain and refill the transmission: tube snakes, a suction probe and fitting, a feed line, and a vessel to hold the old fluid.

The snakes or probes will pull out all the old fluid, and the feed line will pour new fluid into the car’s transmission. The vessel will hold all of the old fluid until it can be safely disposed of.

How to Correct the Overfilled Transmission Problem

Overfilling the transmission can cause damage to the transmission. The transmission will need to be drained to compensate for the extra fluid taken in because of overfilling. The symptoms to watch for are shifted gears and slipping gears. Take your vehicle to a shop for an inspection.

Here are 5 common symptoms of overfilled transmission:

Slipping or Failing to Shift Gear

Slipping or failing to shift gear is a symptom of overfilled transmission. Overfilling your transmission will cause it to fail to shift or slip when a gear is shifted.

Shifted Gears that Feel Rough

Another sign of overfilled transmission is shifted gears that feel rough. The rough shifting is related to the amount of fluid that flows through the transmission. If you continue to fill the transmission to the point that it feels rough when shifting gears, then you should find a repair shop to repair the overfilled transmission.

Rattling While Rolling

One of the 5 common symptoms of overfilled transmission is a rattling sound coming from the transmission when you are rolling down the road. This sound is normally felt in the vehicle with a small amount of driving. The rattling sound may actually be heard inside the car. This sound is another sign of overfilled transmission.

Slipping or Failing to Go into Gear


Transmission fluid is a very important part of your vehicles engine. It is the life blood. It is responsible for keeping the car in motion and coordinating the functions of all the other vehicles parts.

Without transmission fluid, your car would not be able to function properly and, without a doubt, would not last as long as it does.

Because of this, you need to make sure the fluid is kept at the right level and that it is changed a few times a year to avoid any issues that can come up if you don’t.

The end result of this transmission fluid is brown or red. You will know it’s time to have the fluid changed if you notice fluid leaking out of your car. It will also make a metal grinding or slapping sound when you drive.

The best way to know what the required fluid change intervals are to check your vehicle’s owner’s manual. Is it getting too late to do that? Don’t worry.

The signs and symptoms we’ve described in this guide will give you a pretty good indication of if you need to change your transmission fluid or not.