Hayden 677 Transmission Cooler

The Hayden Automotive 677 transmission cooler offers phenomenal transmission fluid cooling which will keep your vehicle’s transmission temperature in a suitable range. Just like other Hayden trans coolers, the 677 is designed using a rugged plate and fin construction. This allows the cooler to not only disperse heat efficiently to cool your vehicle’s transmission, but can withstand the rigors of daily driving abuse.

The Hayden 677 comes with pre-drilled mounting holes and barb style fittings to make installation quick and easy. If you’re looking for a highly efficient easy to install transmission cooler, the Hayden 677 is perfect for any car or small truck or SUV that does not require extensive transmission cooling.

The Hayden 677 is one of the best small transmission coolers on the market, just like the Hayden 687. So much so that it is also recommended in our transmission coolers buyer’s guide because it is highly versatile and is a great option for the enthusiast on a budget.

Transmission CoolerGVWRType Of CoolerPrice

Hayden 677 transmission cooler - Transmission Cooler Guide

20,000Plate & FinShop Now

Hayden 677 Specs

The Hayden 677 is built with  an 11″ x 7 1/2″ x 3/4″ body that is not only large enough to efficiency cool transmission fluid, but is still thin enough to mount in most common locations without much modification. In addition, the Hayden 677 is rated at 20,000 GVW which allows for up to 2,500 pounds of tow capacity. This is suitable for most mid-size and full-sized cars as well as pickup trucks and SUV’s.

For the cost, the Hayden 677 is an excellent option for those looking to keep transmission temperatures down without breaking the bank.

Cooler Dimensions: 11″ x 7 1/2″ x 3/4″

GVW: 20,000 pounds

Fitting Size: 3/8″ barb

Recommended Uses

  • Daily Driven Cars, Trucks & SUV’s

Based solely on the size of the Hayden 677, it is recommended for use on most standard vehicles. With it’s average sized construction, this cooler will easily handle most situations that you will typically encounter.

Although it is rated to 20,000 GVW, it would be best to only tow up to 2,500 as recommended by Hayden.  Despite this recommendation, we believe you can easily tow within most vehicles limits, but you will need to watch trans temps as this isn’t the most ideal trans cooler for towing.

Hayden 677 Installation

The Hayden 677 comes as a universal trans cooler kit, so installation is dependent on each vehicle.  The kit comes with extra transmission hose, mounting brackets with nuts and bolts, various barb fittings, hose clamps, spacers and mounting ties. Since most people will opt to mount the transmission cooler in front of the air conditioning condenser and  radiator, the mounting pieces will be enough for most installs.

It is recommended to run this cooler in addition to the stock cooler in the radiator because this is not large enough to use as a stand alone cooler.

Hayden 677 Pros & Cons


  • Easy To Install
  • Plate & Fin Construction
  • 20,000 GVW Rating
  • Includes Complete Installation Kit
  • Cost – Can Be Found Under $40


  • Barb Fittings

Hayden 677 Information

While the Hayden 677 transmission cooler is small, it is a great cooler for the size and cost. Many users will agree that this cooler is hard to beat and does a phenomenal job at keeping trans temps lower in their small and mid-sized vehicles. 

With over 250 reviews with a 4.5 rating, the Hayden 677 is definitely a viable option for those looking to increase transmission cooling without breaking the bank.

Keeps my transmission running cooler on average!
Works great on my Rav4, saw an immediate drop in temps


With the combination of being a highly efficient plate and fin style transmission cooler and its  affordability, the Hayden Automotive 677 transmission cooler is by far one of the best transmission coolers available.  The cooler offers a 20,000 GVW capacity that allows for ample trans cooling in most common applications and has a very low price for the performance. 

Another great benefit the Hayden 677 offers is that it comes with a complete installation kit with extra transmission hose, clamps, and everything else needed for an easy installation.  While the kit comes with various fittings, it might be necessary to purchase additional fittings, depending on how you plan to route the fluid lines.

Overall, it is hard to beat this cooler, and for the budget minded driver with typical transmission cooling needs, the Hayden 677 is a perfect option. 

Get The Best Price On Hayden 677 Transmission Coolers

Hayden 677 transmission cooler - Transmission Cooler GuideLower transmission temps with the help of the Hayden 677 today. Shop Now!

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Hayden 677

The Hayden Automotive 677 transmission cooler is a perfect choice for superior transmission fluid cooling. Learn more about the Hayden 677 and its benefits!

Product Brand: Hayden

Editor's Rating:


  • Easy To Install
  • Plate & Fin Construction
  • 20,000 GVW Rating
  • Includes Complete Installation Kit
  • Cost – Can Be Found Under $40


  • Barb Fittings