Best Car Transmission Relays of 2025

Robert Reyes Avatar
Robert Reyes
Last Updated: Jan 2, 2025

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Car transmission relays are essential components of a vehicle's transmission system. They act as a switch that controls the flow of power between different parts of the transmission. Without the proper functioning of these relays, a car's transmission system may fail to shift gears or even break down. There are various types of transmission relays available in the market, including electromagnetic, solid-state, and hybrid relays. Each type has its unique features and benefits, and choosing the right one depends on the specific needs of the vehicle. Car owners should ensure that their transmission relays are regularly inspected and replaced if necessary to ensure smooth and safe driving.

At a Glance: Our Top Picks

Standard Motor Products HR-117 Transmission Relay Assorted Cover #TOP 1
Standard Motor Products HR-117 Transmission Relay Assorted
ftb score rating icon 9.9
Denso 567-0015 Relay Cover #TOP 2
Denso 567-0015 Relay
ftb score rating icon 9.8
Denso 567-0005 Relay Cover #TOP 3
Denso 567-0005 Relay
ftb score rating icon 9.6

Top 10 Car Transmission Relays

#TOP 1

Standard Motor Products HR-117 Transmission Relay Assorted

HR-117
Assorted
One Size
Standard Motor Products HR-117 Transmission Relay Assorted Cover
Standard Motor Products HR-117 Transmission Relay Assorted, One Size

The Standard HR-117 Relay is a high-quality car ignition relay manufactured by STANDARD IGN. Made in China, this relay is designed to provide reliable transmission control for your vehicle. With a package height of 2.082 inches, length of 7.381 inches, and width of 5.412 inches, this relay is compact and easy to install. The HR-117 Relay is known for its durability and performance, ensuring smooth transmission operation. Whether you're a car enthusiast or a professional mechanic, this relay offers convenience and peace of mind. Upgrade your car's ignition system with the Standard HR-117 Relay and experience enhanced transmission control.

What We Like
Reliable transmission control
Durable and high-performance
Compact and easy to install
#TOP 2

Denso 567-0015 Relay

567-0015
Multi
Denso 567-0015 Relay Cover
Denso 567-0015 Relay

Denso Car Relay is a high-quality car transmission relay from Japan. This relay is a crucial component in your car transmission system. It can help to control the electrical flow to various parts of your car, ensuring that they work properly. With a weight of only 0.045 kilograms and dimensions of 3.81 cm L X4.826 cm W X5.588 cm H, this relay is compact and easy to install. The Denso Car Relay is a reliable product that can help you maintain the efficiency and safety of your car.

What We Like
Compact
Reliable
High-quality
#TOP 3

Denso 567-0005 Relay

567-0005
Multicolor
Denso 567-0005 Relay Cover
Denso 567-0005 Relay

The Denso Relay is an OEM identical relay designed for car transmission systems. Made in China, this relay offers reliable performance and is a perfect replacement for your vehicle's worn-out relay. With a compact size of 4.572 L x 3.555 H x 5.334 W (centimeters) and a lightweight package weighing only 0.35 pounds, it is easy to install and won't add unnecessary weight to your car. The Denso Relay is built to meet OEM standards, ensuring compatibility and optimal functionality. It is an essential component for maintaining the efficiency and smooth operation of your car's transmission system.

What We Like
Reliable performance
Compact size
Lightweight design
#TOP 4

Denso Relay 567-0004

567-0004
Denso Relay 567-0004 Cover
Denso Relay - 567-0004

The Denso Relay is a reliable component designed for car transmission systems. Measuring 5.334 cm in length, 4.572 cm in width, and 3.555 cm in height, it fits conveniently into various automotive setups. With a single unit per package, it offers an easy solution for those needing to replace a faulty relay. Made in China, this product ensures quality and durability, making it a dependable choice for your vehicle's electrical needs. By using the Denso Relay, you can enhance your car's performance and maintain its operational efficiency.

What We Like
Compact size for easy installation
Single unit packaging
Reliable performance
Quality manufacturing
#TOP 5

Mopar 56029766AC Electrical Relay

56029766AC
Mopar 56029766AC Electrical Relay Cover
Mopar 56029766AC RELAY ELECTRICAL

The Mopar Electrical Relay is an original equipment manufacturer (OEM) part specifically designed for your vehicle. With part number 56029766AC, this relay is manufactured to exact specifications, ensuring a precise fit and reliable performance. It plays a crucial role in the electrical system of your car, helping to control various functions effectively. By using this high-quality relay, you can enjoy peace of mind knowing that it will perform reliably and enhance the overall functionality of your vehicle.

What We Like
OEM quality assurance
Perfect fit for your vehicle
Reliable electrical performance
Enhances vehicle functionality
#TOP 6

URO Parts 2015403745 Overload Relay

2015403745
White & Brown
4.3 Inch
URO Parts 2015403745 Overload Relay Cover
URO Parts 2015403745 Overload Protection Relay, White & Brown

The URO Parts Overload Relay is designed with a 9-pin configuration, making it suitable for late-model vehicles. Its compact dimensions of approximately 10.9 cm by 5.8 cm by 4.3 cm ensure it can fit easily within your car's system. As an essential auto part, this relay helps protect against electrical overloads, which can prevent potential damage to your vehicle's transmission. With a single unit included in the package, you can conveniently replace your old relay and enhance your car's reliability, ensuring smooth performance on the road.

What We Like
Compact design
9-pin compatibility
Electrical overload protection
Easy replacement
#TOP 7

URO Parts Multi Purpose Relay 7M0951253A

7M0951253A
URO Parts Multi Purpose Relay 7M0951253A Cover
URO Parts 7M0951253A Multi Purpose Relay

The URO Parts Relay is designed specifically for your vehicle, ensuring a perfect fit and optimal performance. Its compact size, measuring just 0.1 L x 1.25 H x 1.25 W inches, makes installation straightforward and hassle-free, allowing you to save time and effort. Weighing only 0.1 pounds, this relay is lightweight, which can help reduce overall vehicle weight for better efficiency. Manufactured in China, you can trust that it meets industry standards for quality and reliability, giving you peace of mind while driving.

What We Like
Vehicle-specific fit
Compact size for easy installation
Lightweight design
Reliable quality
#TOP 8

Denso 567-0020 Relay

567-0020
Denso 567-0020 Relay Cover
Denso 567-0020 Relay

Denso Auto Relay is a high-quality car transmission relay from Japan. With package dimensions of 4.6 cm L x 5.0 cm W x 36.1 cm H and a weight of only 0.1lbs, it is a compact and lightweight option for your car. Made by a trusted brand, this relay is built to last and ensures that your car's transmission runs smoothly. It is easy to install and will help prolong the life of your vehicle. The country of origin, Japan, is known for producing reliable car parts, giving you peace of mind that you are getting a quality product. The Denso Auto Relay is a must-have for any car owner looking for a reliable and efficient transmission relay.

What We Like
Compact
Lightweight
Easy to install
High-quality
Reliable
#TOP 9

Denso 567-0021 Relay

567-0021
Denso 567-0021 Relay Cover
Denso 567-0021 Relay

Denso Car Relay is a high-quality car transmission relay that is made in Japan. With its package dimensions of 2 L x 1.38 H x 1.75 W (inches) and lightweight of 0.1 pounds, it is easy to install in your vehicle. The relay is designed to be long-lasting and reliable, ensuring that your car's transmission system is functioning smoothly. As a product of Denso, a trusted brand in the automotive industry, you can count on its quality and performance. Whether you are a professional mechanic or a DIY car enthusiast, Denso Car Relay is a great choice for your car's transmission system.

What We Like
Compact size
Lightweight
Reliable performance
#TOP 10

Hyundai Relay Assembly 95220-3B200

95220-3B200
Hyundai Relay Assembly 95220-3B200 Cover
Genuine Hyundai 95220-3B200 Relay Assembly

The Hyundai Relay Assembly is an authentic OEM part designed specifically for your vehicle. This means you are getting a component made to the same high standards as the original, ensuring reliability and performance. As an exact match for the part that came with your car, it guarantees a seamless fit, making installation straightforward. Plus, its OEM quality means you can trust it to function just like the original, providing peace of mind and enhancing your vehicle's performance.

What We Like
Authentic OEM quality
Direct fit for easy installation
Reliable performance
Buying Guide Image

Frequently Asked Questions (FAQs)

1. What are the symptoms of a bad transmission relay?

Some symptoms of a bad transmission relay include unpredictable shifting, trouble shifting into higher gear, trouble downshifting, getting stuck in the same gear, poor fuel economy, and the check engine light coming on.

2. Can I drive with a bad relay?

Driving with a bad relay is not recommended. If the ignition relay fails while the engine is running, it will cut off power to the fuel pump and ignition system, causing the vehicle to stall immediately.

3. What sensors control transmission shifting?

The Transmission Range Sensor (TR sensor) controls transmission shifting. It informs the PCM (Powertrain Control Module) about the position of the transmission shifter, allowing the PCM to enable or disable specific gears. A failure in the TR sensor can result in incorrect gear starts, lack of upshifts, or a feeling of falling out of gear.

4. What happens when a TCM goes out?

When the Transmission Control Module (TCM) fails, it can cause symptoms such as slow acceleration, gear slippage, and an inability to shift out of neutral. If you experience any of these signs, it is recommended to have your vehicle inspected and repaired by a professional.

5. What causes a relay to fail?

Relays can fail due to factors like worn-out springs, poor contact alignment, and open coils. The selection of the appropriate relay type for a specific application is crucial for ensuring reliability. Poor design practices can also contribute to relay failures.

6. Can you drive with a bad transmission control module?

Driving with a faulty Transmission Control Module (TCM) is not safe. A malfunctioning TCM can cause unpredictable shifting gears, making the vehicle highly unpredictable. If you notice any signs of TCM failure, it is recommended to take your vehicle to a professional for repairs.

7. Is there a way to reset a transmission control module?

To reset a vehicle's Transmission Control Module (TCM), turn off the ignition and wait for 5 to 10 seconds. Start the engine and let it idle for several seconds. Turn off the ignition again and wait for 30 to 40 seconds. Repeat this process 2 to 3 times to reset the TCM.

8. What is the most common problem found with a relay failure?

The most common failure mechanisms of relays are contamination and mechanical wear of the internal switching elements. However, solid-state relays are generally more reliable and predictable for long-life applications, except for special high voltage and high-temperature situations.

Editor's Notes

During our car transmission relay research, we found 24 car transmission relay products and shortlisted 10 quality products. We collected and analyzed 4,488 customer reviews through our big data system to write the car transmission relays list. We found that most customers choose car transmission relays with an average price of $21.13.

The car transmission relays are available for purchase. We have researched hundreds of brands and picked the top brands of car transmission relays, including Standard Motor Products, Denso, Mopar, URO Parts, HYUNDAI. The seller of top 1 product has received honest feedback from 385 consumers with an average rating of 4.7.

Written by
Robert Reyes Avatar

Robert Reyes is a dedicated writer from San Francisco with a bachelor of degree in mechanics and a bachelor of degree in marketing. He focuses on making some complicated topics simple and enjoys explaining complex and technical things in an easy-to-understand way.