Need car parts? Select your vehicle
Reading Time: 4 minutes
Summary
  • The common symptoms of an obstructed transmission filter include abnormal shifting, noises from the transmission pump, and contaminated transmission fluid.
  • The PCM will also illuminate the check engine light and record a diagnostic trouble code (DTC) if it detects a transmission issue caused by low fluid pressure.
  • The symptoms could vary depending on the vehicle’s year, make, and model.

Automatic transmissions have a transmission filter (or strainer) that traps contaminants and debris before they circulate throughout the transmission. On many vehicles, the filter is a maintenance item that requires routine replacement.

If the filter is not serviced in accordance with the vehicle manufacturer’s maintenance schedule, it may eventually become obstructed, resulting in one or more noticeable symptoms.

How Does a Transmission Filter Work?

All automatic transmissions have a filter made of paper and/or synthetic materials (or a strainer made from woven metal). The filter is located in the transmission fluid pan and positioned at the transmission pump’s inlet.

automatic transmission filter
The automatic transmission filter is important because it traps contaminants so that they do not enter the pump and get distributed throughout the transmission.

When the vehicle’s engine is running, the pump, which is driven off the engine by the torque converter, starts pulling fluid from the pan through the filter. From there, the pump pressurizes the fluid and distributes it to the various passages in the transmission’s valve body. The pressurized fluid acts on the control devices (clutches and bands) that cause the transmission to shift gears.

See also  Is Your Car Stuck In Neutral? Here’s Why

The transmission filter is important because it traps contaminants so that they do not enter the pump and get distributed throughout the transmission. Unfortunately, the role of the transmission filter makes it susceptible to obstruction from dirt and debris.

When the filter becomes obstructed, the pump will be starved of fluid, resulting in a low fluid pressure condition inside the transmission.

Clogged Transmission Filter Symptoms

Many other problems can mimic an obstructed transmission filter. What’s more, filters often become clogged due to internal transmission problems that result in excessive debris. So, you (or your mechanic) should diagnose the vehicle thoroughly before assuming the filter is to blame for any of the symptoms listed below.

With that in mind, let’s take a look at the most common symptoms of a clogged transmission filter.

Abnormal Shifting

One of the most common signs of a clogged transmission filter is abnormal shifting. Automatic transmissions often begin to “slip” when one or more of the control devices fail to hold due to low fluid pressure. This slippage results in an increase in engine RPMs without an increase in vehicle speed. You may also notice other shift quality issues if the transmission filter is clogged.

Noise from the Transmission Pump

An obstructed transmission filter can starve the pump of fluid, causing the pump to make a whining noise that coincides with engine speed.

Burnt or Contaminated Transmission Fluid

If the filter is obstructed, the transmission will experience overheating due to lack of lubrication. As a result, the fluid will often be dark in color and smell burnt. Once the transmission pan is removed, you may also find signs of excessive friction material and/or metal debris in the bottom of the pan.

See also  P2715 Code: Pressure Control Solenoid "D" Stuck On
aftermarket transmission filter
If the transmission filter is obstructed, it will experience overheating due to lack of lubrication, and may cause the fluid to be dark in color and have a burnt smell.

Illuminated Warning Lights

On modern vehicles, the transmission control module (TCM) monitors transmission operation. If the module detects a problem with the transmission due to low fluid pressure, the device will turn on the check engine light and store a diagnostic trouble code (DTC) in its memory. Some vehicles may also turn on a separate transmission warning light when there’s a problem.

Transmission Filter FAQ

How to Unclog a Transmission Filter

A transmission filter cannot be unclogged—it must be replaced. The good news is, replacing a transmission filter or transmission strainer is generally a fairly inexpensive and straightforward repair, as long as there hasn’t been any subsequent damage to the transmission.

How Much Does it Cost to Fix a Clogged Transmission Filter?

As is noted above, a clogged transmission filter must be replaced. A professional repair shop will typically replace the filter as part of a transmission service. Usually, the service will cost somewhere between $150 and $300. Of course, the exact cost will vary depending on a variety of factors, such as the year, make, and model of your vehicle.

Also, it’s important to point out that the transmission may have suffered internal damage as a result of the clogged filter. In such a scenario, the transmission will either need to be rebuilt or replaced—and that can cost thousands of dollars.

See also  P0768 Code: Shift Solenoid “D” Electrical

Get a Top-Notch Transmission Filter for Your Ride

A clogged transmission filter can cause issues like abnormal shifting and transmission fluid contamination, which can lead to a plethora of problems that are hard to fix. If yours is clogged or obstructed, don’t think twice about replacing it. Find and order a new transmission filter for your ride in minutes here at CarParts.com.

Simply go to  CarParts.com and enter your ride’s year, make, and model into our vehicle selector to view compatible transmission filters. Our filters are available at unbeatable prices to give you the best value for your money. We source them from top industry brands, so you can be sure they’ll perform like your factory filter.

Order now, and get your transmission filter in as fast as a few days. Our warehouses are strategically located across the country to ensure fast and efficient shipping. If you aren’t satisfied with your purchase, we implement a 60-day return policy that guarantees you get your money back. We have a round-the-clock customer service team ready to assist you. 
Don’t put off replacing your clogged transmission filter. Take a look at our selection of transmission filters today!

About The Author
Written By Automotive Subject Matter Expert at CarParts.com

Mia Bevacqua has over 14 years of experience in the auto industry and holds a bachelor’s degree in Advanced Automotive Systems. Certifications include ASE Master Automobile Technician, Master Medium/Heavy Truck Technician, L1, L2, L3, and L4 Advanced Level Specialist. Mia loves fixer-upper oddballs, like her 1987 Cavalier Z-24 and 1998 Astro Van AWD.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

File Under : DIY , Transmission Tagged With :
bumpers and components
Subscribe
Notify of
guest
0 Comments
Inline Feedbacks
View all comments

View all Questions & Answers

expand_more
CarParts.com Answers BE PART OF OUR COMMUNITY: Share your knowledge & help fellow drivers Join Now
Copyright ©2023 CarParts.com, Inc. All Rights Reserved.