Best Aftermarket Relays

Are you looking for the best aftermarket relays?
We provide a curated list of top-rated relays to help you upgrade your vehicle’s electrical system.

Aftermarket relays are essential for keeping your vehicle’s electrical systems running smoothly. Whether you’re upgrading, replacing, or adding new features, the right relay can make all the difference. We’ve gathered the best options to help you find the perfect fit for your needs.

Relays come in various types, from waterproof to high-power, each designed for specific tasks. They ensure reliable performance and longevity for your car, truck, or boat. Choosing the right one can save you time and money.

Ready to upgrade your vehicle’s electrical system? Our guide breaks down the top aftermarket relays, making it easy to find the one that matches your needs. Let’s get started!

List of Top 10 Aftermarket Relays

Title	Best For	Price
5-pin 40/30Amp 12V DC Waterproof Automotive Relay with Heavy-Duty Wire	This 5-pin 40/30Amp 12V DC Waterproof Automotive Relay is perfect for anyone working on cars, trucks, or boats. It’s great for heavy-duty wiring projects where reliability and durability matter.	View on Amazon (paid link)
Gebildet 2pcs 12V 40A 4 Pin SPST Car Relay Harness JD1912, 12AWG Harness Sockets with Built-in Diode for Automotive Truck Van Boat Motorcycle	This product is perfect for anyone who needs reliable and durable relays for their vehicle. Whether you own a car, truck, van, boat, or motorcycle, these relays with built-in diodes will protect your electrical components and ensure smooth operation.	View on Amazon (paid link)
2-Pack P6STD F0AB/FOAB-14B192-AA 5-Pin SPDT Automotive Relay, 12V 40A Multi-Purpose Aftermarket Replacement Relay for Select Ford Vehicles, Check Pin Layout, Not for 4-Pin Sockets	This 2-pack replacement relay is perfect for DIY car owners and local mechanics seeking a simple, direct plug-in fix for their vehicle. It is the best choice for select Ford models needing a strong 5-pin relay to power key systems.	View on Amazon (paid link)
4 PCS Relays, 5 Pin Relay, 40A Waterproof Car Relays, 12V Relay Switch	This 4 PCS Relays set is perfect for anyone who needs reliable, waterproof relays for their car, boat, or electric vehicle. Whether you’re replacing old parts or working on a new project, these easy-to-install relays are built to last in any environment.	View on Amazon (paid link)
FASTSTORM Dual Electric Fan Relay Kit Electric Radiator Fan Kit Temperature Sensor Switch 185 On 175 Off Automotive Wiring Kit 60 Amp Cooling Fan Relay Switch Kit 4 Pin Waterproof Relay Kit	This dual electric fan relay kit is perfect for anyone who wants to keep their vehicle’s engine cool and prevent overheating. It’s great for cars, trucks, and boats, whether you’re upgrading or replacing old parts.	View on Amazon (paid link)
Hoypeyfiy 4PCS Power Trim and Tilt Relay 5 Pin 40A 12V Waterproof Car Relays 584416 586224 18-570 Replacement for Johnson Evinrude Outboard Marine Corp OMC；	This relay pack is perfect for boat owners who need a simple replacement part. It is also great for mechanics doing fast repairs on marine motors.	View on Amazon (paid link)
True MODS 12V Automotive Waterproof 5-Pin Prewired Relay Fuse Box Block Kit	This True MODS 12V Automotive Waterproof 5-Pin Prewired Relay Fuse Box Block Kit is perfect for car enthusiasts and DIY lovers who want to organize and upgrade their vehicle’s electrical system. It’s easy to install and built tough for any weather or terrain.	View on Amazon (paid link)
(Pack of 4) High Power 4-Pin Fuse Box Relay 13500114/8385 – 12V 40A	This 4-pack of high-power relays is perfect for car owners who need reliable replacements or backups. It’s great for DIY fixes and works with many GM models.	View on Amazon (paid link)
Weasch 12V 6 Way Pre-Wired Fuse Relay Box Kit with 4 x 40A 4-Pin Relays	This easy kit is perfect for DIY drivers who love custom rides. It is great for trucks and SUVs needing safe power.	View on Amazon (paid link)
Yourkar 2 PCS Car AC Relay, G8HL-H71-12VDC 4 Pins AC and Starter Relays, Multiple Power Relay Assembly Starter Relays for Driving Lights/Air Conditioning/Fans, Car Accessories	This compact car relay is perfect for DIY car owners and local mechanics needing a simple, reliable way to fix car air conditioning, lights, or starters. It is a must-have tool for quick vehicle repairs at home.	View on Amazon (paid link)

Detailed Reviews

We found the best aftermarket relays for your vehicle. Our quick guide lists the top ten choices for you. Enjoy simple, safe power for your car projects. Find the perfect fit for your budget today.

1. 5-pin 40/30Amp 12V DC Waterproof Automotive Relay with Heavy-Duty Wire

The 5-pin 40/30Amp 12V DC Waterproof Automotive Relay is a heavy-duty solution for your vehicle’s electrical needs. It’s built to handle 12 volts and works best when used below its maximum capacity.

This relay is waterproof and dustproof, making it reliable for tough conditions. It has 5 prongs and uses tinned copper wire for strong connections.

Always handle with care when installing to avoid bending the connectors. Its 12V DC coil and 1.8W power ensure efficient performance for your automotive projects.

Pros	Cons
Waterproof and dustproof for reliable performance in tough conditions. Heavy-duty 12 AWG wire ensures strong and durable connections. 12V DC compatibility works perfectly for automotive systems. 5-pin SPDT design allows easy and flexible installation.	Not fully waterproof, only water-repellent and dustproof. Female connectors bend easily if forced into socket. Must stay below 10-15% of rated capacity for safe use.

Perfect For:

This 5-pin 40/30Amp 12V DC Waterproof Automotive Relay is perfect for anyone working on cars, trucks, or boats. It’s great for heavy-duty wiring projects where reliability and durability matter.

Ready to Purchase?

View Price on Amazon (paid link)

Best Leak Resistant Designs

2. Gebildet 2pcs 12V 40A 4 Pin SPST Car Relay Harness JD1912, 12AWG Harness Sockets with Built-in Diode for Automotive Truck Van Boat Motorcycle

The Gebildet 2pcs 12V 40A 4 Pin SPST Car Relay Harness is a reliable and efficient solution for your vehicle’s electrical needs. It comes with a built-in diode that protects your components from voltage spikes.

This compact and low-power relay has high sensitivity and long-lasting performance, with a life expectancy of 100,000 electrical operations and 10,000,000 mechanical operations. It works with 8V or 12V systems and has low contact resistance.

Pros	Cons
Built-in diode protects your vehicle’s electrical system from damage. Compact design saves space in your car, truck, or boat. High reliability with 100,000 electrical operations guaranteed. Low power consumption ensures efficient performance for your vehicle.	No waterproof design, limits outdoor use. Requires professional installation, not DIY friendly. Limited compatibility with non-standard systems.

Perfect For:

This product is perfect for anyone who needs reliable and durable relays for their vehicle. Whether you own a car, truck, van, boat, or motorcycle, these relays with built-in diodes will protect your electrical components and ensure smooth operation.

Ready to Purchase?

View Price on Amazon (paid link)

3. 2-Pack P6STD F0AB/FOAB-14B192-AA 5-Pin SPDT Automotive Relay, 12V 40A Multi-Purpose Aftermarket Replacement Relay for Select Ford Vehicles, Check Pin Layout, Not for 4-Pin Sockets

2-Pack P6STD F0AB/FOAB-14B192-AA 5-Pin SPDT Automotive Relay, 12V 40A Multi-Purpose Aftermarket Replacement Relay for Select Ford Vehicles, Check Pin Layout, Not for 4-Pin Sockets

Need a reliable relay for your Ford? This 2-pack of P6STD F0AB/FOAB-14B192-AA relays is designed for select Ford vehicles. Verify compatibility before buying to ensure a perfect fit.

These 5-pin SPDT relays handle 12V 40A and work with various systems like fuel pumps, horns, or starters. Not for 4-pin sockets—check your vehicle’s relay setup first.

Easy plug-in replacement, no wiring changes needed. Includes two relays for replacement or backup.

Pros	Cons
Exact fit for select Ford vehicles with 5-pin SPDT relays. Plug-and-play design for easy, no-wiring installation. Multi-purpose use in fuel pump, starter, or horn systems. 2-pack for replacement and backup needs.	Not universal: Only fits specific 5-pin sockets, check before buying. No wiring fix: Requires exact match, no room for error. Diagnose first: Relay may not fix all issues, check other parts.

Perfect For:

This 2-pack replacement relay is perfect for DIY car owners and local mechanics seeking a simple, direct plug-in fix for their vehicle. It is the best choice for select Ford models needing a strong 5-pin relay to power key systems.

Ready to Purchase?

View Price on Amazon (paid link)

4. 4 PCS Relays, 5 Pin Relay, 40A Waterproof Car Relays, 12V Relay Switch

Get reliable performance with these 40A waterproof car relays. Made from quality materials, they ensure excellent heat dissipation and long-term durability.

Easy to install, widely applicable, and fully waterproof, these relays are perfect for automotive and marine use.

Pros	Cons
Flame-retardant material ensures safety and durability. IP67 waterproof design works reliably in humid conditions. Easy installation with no extra tools needed. Versatile use for cars, boats, and more.	No mounting hardware included, may need extra parts for setup. Limited compatibility with non-standard or older vehicle models. No instructions provided, might confuse first-time installers.

Perfect For:

This 4 PCS Relays set is perfect for anyone who needs reliable, waterproof relays for their car, boat, or electric vehicle. Whether you’re replacing old parts or working on a new project, these easy-to-install relays are built to last in any environment.

Ready to Purchase?

View Price on Amazon (paid link)

5. FASTSTORM Dual Electric Fan Relay Kit Electric Radiator Fan Kit Temperature Sensor Switch 185 On 175 Off Automotive Wiring Kit 60 Amp Cooling Fan Relay Switch Kit 4 Pin Waterproof Relay Kit

FASTSTORM Dual Electric Fan Relay Kit Electric Radiator Fan Kit Temperature Sensor Switch 185 On 175 Off Automotive Wiring Kit 60 Amp Cooling Fan Relay Switch Kit 4 Pin Waterproof Relay Kit

The FASTSTORM Dual Electric Fan Relay Kit keeps your engine cool and prevents overheating. It works with 10″ to 16″ fans and includes a 60 amp relay. Perfect for upgrades or replacements.

It has a temperature-controlled switch that turns fans on at 185°F and off at 175°F. This saves energy and extends engine life.

The waterproof design works in all weather. It’s easy to install and fits cars, trucks, and boats. A reliable choice for efficient cooling.

Pros	Cons
Efficient cooling prevents engine overheating for reliable performance. Temperature-controlled fans activate at 185°F, turn off at 175°F. Easy installation with clear wiring diagram and all parts included. Waterproof fuse holders ensure durability in all weather conditions. Widely compatible with trucks, cars, boats, and more vehicles.	No fan included, just the relay kit and wiring components. Requires basic wiring knowledge for proper installation. Not plug-and-play, customization may be needed for some vehicles.

Pros

Cons

Efficient cooling prevents engine overheating for reliable performance.
Temperature-controlled fans activate at 185°F, turn off at 175°F.
Easy installation with clear wiring diagram and all parts included.
Waterproof fuse holders ensure durability in all weather conditions.
Widely compatible with trucks, cars, boats, and more vehicles.

No fan included, just the relay kit and wiring components.
Requires basic wiring knowledge for proper installation.
Not plug-and-play, customization may be needed for some vehicles.

Perfect For:

This dual electric fan relay kit is perfect for anyone who wants to keep their vehicle’s engine cool and prevent overheating. It’s great for cars, trucks, and boats, whether you’re upgrading or replacing old parts.

Ready to Purchase?

View Price on Amazon (paid link)

6. Hoypeyfiy 4PCS Power Trim and Tilt Relay 5 Pin 40A 12V Waterproof Car Relays 584416 586224 18-570 Replacement for Johnson Evinrude Outboard Marine Corp OMC；

Hoypeyfiy 4PCS Power Trim and Tilt Relay 5 Pin 40A 12V Waterproof Car Relays 584416 586224 18-570 Replacement for Johnson Evinrude Outboard Marine Corp OMC；

The Hoypeyfiy 4PCS Power Trim and Tilt Relay is a high-quality aftermarket product. It’s designed to meet or exceed OEM specs. This ensures reliable performance for your marine motor.

It’s a 40 Amp/12 Volt relay made for marine outboard use. The 5-pin design makes installation easy. No extra tools are needed for quick replacements.

This pack includes 4 relays for multiple replacements or backup inventory. It’s compatible with Johnson, Evinrude, and OMC motors. Replace old parts with confidence.

Pros	Cons
Reliable performance with premium quality, meeting OEM specs. Easy installation, no extra tools needed, fits tight spaces. Wide compatibility for Johnson, Evinrude, and OMC motors. Value pack of 4 relays for multiple replacements or backups.	Not for all motors, check compatibility before buying. No tools included, you’ll need your own for installation. Bulk pack, might be more than you need for one repair.

Perfect For:

This relay pack is perfect for boat owners who need a simple replacement part. It is also great for mechanics doing fast repairs on marine motors.

Ready to Purchase?

View Price on Amazon (paid link)

7. True MODS 12V Automotive Waterproof 5-Pin Prewired Relay Fuse Box Block Kit

Organize your car wiring with this waterproof power block. It keeps your electric circuits neat and simple. The prewired harness makes setup fast.

This weatherproof box is built from strong nylon to last for years. The universal Z brackets let you mount it easily under your hood.

You get 6 relays, fuses, and color-coded wires in the box. Enjoy robust 12 AWG power wires for your high-power relays.

Pros	Cons
Organize and control multiple circuits with six relay sockets. Waterproof and durable for all-weather use. Easy install with color-coded wires and universal brackets. Complete kit includes relays, fuses, and connectors.	No instructions included, making setup tricky for beginners. Limited fuse slots may not meet all wiring needs. Bulkier design could be hard to fit in tight spaces.

Perfect For:

This True MODS 12V Automotive Waterproof 5-Pin Prewired Relay Fuse Box Block Kit is perfect for car enthusiasts and DIY lovers who want to organize and upgrade their vehicle’s electrical system. It’s easy to install and built tough for any weather or terrain.

Ready to Purchase?

View Price on Amazon (paid link)

8. (Pack of 4) High Power 4-Pin Fuse Box Relay 13500114/8385 – 12V 40A

This 4-pack of high-power relays is a perfect fit for many GM vehicles. It works with Buick, GMC, Cadillac, and more. Use it for AC, lights, fuel pumps, and other parts.

The relays are built to last in tough conditions. They are easy to install and come at a great price.

Pros	Cons
Direct GM replacement, fits Buick, GMC, Cadillac, and more. Powers multiple systems like AC, lights, and fuel pumps. Built tough, resists heat, wear, and corrosion. Easy DIY install, compact and hassle-free wiring. Great value, 4 relays in one affordable pack.	No instructions included for DIY installation. Limited compatibility with non-GM vehicles. Bulk pack may be more than needed for small repairs.

Perfect For:

This 4-pack of high-power relays is perfect for car owners who need reliable replacements or backups. It’s great for DIY fixes and works with many GM models.

Ready to Purchase?

View Price on Amazon (paid link)

9. Weasch 12V 6 Way Pre-Wired Fuse Relay Box Kit with 4 x 40A 4-Pin Relays

The Weasch 12V 6-Way Fuse Relay Box Kit is ready to install right out of the box. It includes four 40A relays and six blade fuses for easy customization. The dustproof shell keeps circuits safe from dirt and debris.

This kit offers double protection for your vehicle’s electrical system. Always check mounting space and current limits before installing for best results.

Pros	Cons
Plug-and-play design for easy installation right out of the box. Double protection with relays and fuses for safe electrical circuits. Dustproof shell keeps circuits safe from dirt and debris. Versatile 12V solution for custom builds and vehicle upgrades.	Not waterproof, only dustproof and handles light splashes. Limited to 25A per circuit, may not suit high-power needs. Verify mounting space before buying to avoid fit issues.

Perfect For:

This easy kit is perfect for DIY drivers who love custom rides. It is great for trucks and SUVs needing safe power.

Ready to Purchase?

View Price on Amazon (paid link)

10. Yourkar 2 PCS Car AC Relay, G8HL-H71-12VDC 4 Pins AC and Starter Relays, Multiple Power Relay Assembly Starter Relays for Driving Lights/Air Conditioning/Fans, Car Accessories

Yourkar 2 PCS Car AC Relay, G8HL-H71-12VDC 4 Pins AC and Starter Relays, Multiple Power Relay Assembly Starter Relays for Driving Lights/Air Conditioning/Fans, Car Accessories

The Yourkar 2 PCS Car AC Relay is a must-have for car owners. It controls AC, lights, and fans with ease. Its compact size makes it easy to carry.

Made of high-quality brass, it resists corrosion and ensures long-lasting use. It works well with low or high voltage, making it reliable.

This relay is simple to install and fits most cars. It’s perfect for various car parts, from AC to fuel pumps. A practical choice for smooth car operation.

Pros	Cons
Controls multiple car parts with precision and speed. High-quality brass ensures long-lasting and reliable performance. Compact size, easy to carry and install anywhere. Versatile use for AC, lights, fans, and more.	No installation guide included, might confuse first-time users. Limited compatibility with non-standard car electrical systems. Small size may make it easy to misplace during installation.

Perfect For:

This compact car relay is perfect for DIY car owners and local mechanics needing a simple, reliable way to fix car air conditioning, lights, or starters. It is a must-have tool for quick vehicle repairs at home.

Ready to Purchase?

View Price on Amazon (paid link)

Buying Guide

Aftermarket relays are key to keeping your vehicle’s electrical system running smoothly. Picking the right one can save you time and money.

Choosing the best aftermarket relay can feel overwhelming, but we’re here to help. Whether you’re upgrading or replacing, this guide makes it easy to find the perfect fit for your needs.

Here’s what to consider when buying:

Type of Relay:
Relays come in waterproof, high-power, and other types. Pick one that matches your vehicle’s needs.
Compatibility:
Check if the relay fits your car, truck, or boat. Some are made for specific brands like Ford or GM.
Pin Configuration:
Relays have 4-pin or 5-pin setups. Make sure it matches your vehicle’s system.
Amperage Rating:
Choose a relay with the right amp rating for your electrical load. Common options are 30A or 40A.
Voltage:
Most relays are 12V, but confirm it works with your vehicle’s voltage.
Durability:
Look for waterproof and dustproof relays for long-lasting use in tough conditions.
Ease of Installation:
Pick relays with prewired harnesses or easy plug-in designs for quick setup.
Additional Features:
Some relays have built-in diodes or temperature sensors for extra protection.

With these factors in mind, you’ll find the perfect aftermarket relay for your vehicle. Happy upgrading!