In-Depth Review: Hayden Automotive 678 Rapid-Cool Plate and Fin Transmission Cooler

In-Depth Review: Hayden Automotive 678 Rapid-Cool Plate and Fin Transmission Cooler

I needed a transmission cooler for my ‘05 Toyota Tacoma, and after doing some research, I decided to get this one from Hayden Automotive. I was moving to a different state, and I just didn’t want to risk a breakdown from overheating or hurting my engine or transmission.

After reading that plate and fin coolers are more efficient than tube and fin coolers, I decided to do some research and find my own. The Hayden Automotive plate and fin cooler is suitable for towing up to 5,000 pounds, which was more than enough for what I needed.

What really sold me was buyer feedback noting how easy the transmission cooler was to install. I’m no expert, so I needed installation to be as quick and painless as possible.

What You Should Know

The best transmission coolers are beneficial if you’re hauling heavy loads or just want to improve your fuel economy. I’ve noticed that it helps my ATF stay cool, even when I’m towing. A few things I like about the Hayden transmission cooler includes:

  • It works for trucks, vans, even some motor homes and trailers.
  • It comes with foam pads and zip ties, usually no need to buy an install kit.
  • Quick and easy to install using the pre-drilled mounting brackets.
  • The patented turbulation system decreases the potential for pressure drop.

Additionally, this transmission cooler is great for keeping my truck on the road for a long time to come. While I originally got it to help keep heat from building up while I’m hauling loads, I’ve noticed that it generally keeps my engine and transmission running smoothly, day-to-day.

First Impressions & Installation

Unpacking this product made me confident that installation would be a breeze. The transmission cooler comes with all hardware necessary to mount it properly and securely, so I didn’t need to buy anything else along with it. Here’s what I found when unpacking:

  • The fins are perfectly aligned and micro-louvered.
  • The cooler lays nice and flat.
  • Included brackets, zip ties, and 11/32 hose.

As I prepared to install the transmission cooler, I hoped it would be as easy to install as it seemed (and it was). I measured carefully to make sure the hose was just the right length. I did an auxiliary install after making sure there weren’t any stress points or kinks in the hose.

A few tips to keep in mind, which I learned after doing some research: you’ll want to adjust your ATF levels properly at this point to make sure everything’s good to go. Play with the levels a bit to figure out how much ATF you’ll need for a proper fluid level with your transmission cooler.

After doing this, I decided I needed to add just under 300 mL. I was all set to head out on my move without worrying about overheating.

The foam pads and zip ties worked perfectly for my ‘05 Tacoma, but I know some prefer to buy an additional kit if the 11/32 hose doesn’t fit on what they drive. I found the fit to be snug and just right, which made things easy.

Putting The Transmission Cooler To Use

I bought this kit because I had quite a bit of stuff to haul. I was moving to a different state, so I didn’t want to take any chance that I’d break down along the way. This cooler performed beyond my expectations.

My emperature gauge allows me to see how efficiently it cools my transmission. This cooler safely got me from one state to another without a breakdown or overheating of my system.

Since the move, I’ve kept the cooler installed, and I’ve definitely noticed an improvement in my mileage. No drastic changes but certainly an added benefit and a sense of security on the road.

While I had some friends telling me it wasn’t necessary to buy a cooler, I’m so glad I opted to install one and decide for myself. I didn’t have to worry about overheating or breaking down, and now that it’s installed, I just love having it.

Final Thoughts

Now that I’ve had this cooler installed for a while, it’s safe to say I’m a big fan. Check out some pros and cons of the Hayden Automotive Rapid-Cool Plate and Fin Transmission Cooler.


  • Quick and painless install. Ideal for novice users.
  • It comes with everything you need, not necessary to buy anything else.
  • An extremely well-made and high-quality product.
  • Keeps your car running better for longer.
  • My favorite bonus: improved gas mileage.


  • Make sure you can use an 11/32 hose, I know it doesn’t fit for every vehicle.

Overall, I’d definitely recommend this product and give it a full-star rating. Hayden Automotive has one happy customer here! This transmission cooler is well-made and really stands up to heavy hauling.

This cooler proved to be a good buy on every front. Even if you don’t have a lot of experience with or knowledge about coolers or how to install them, this one is ideal for everyone. I was a little nervous installing it on my own, but it really couldn’t be easier.

I’ve had my transmission cooler installed for a few weeks, and it’s holding up great. It’s running smoothly without causing any sort of pressure drop, and I’ve got my ATF at just the level I need it to be. While I’m no longer hauling my stuff across the country, I just love the benefit of increased gas mileage and knowing that I’m keeping my Tacoma running more efficiently for longer.

Whether you’re looking to ensure you don’t break down while towing or just trying to find a way to save some money on gas, I highly recommend this transmission cooler from Hayden Automotive over any other. Installation is a breeze, and this product really delivers!

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.