Hayden Automotive678 Universal Rapid-Cool 9.5” x 11” Add-On Transmission Cooler – Not for Direct Replacement of the OE Cooler

I cannot say how I truly feel about this unit seeing it has only been installed for 2 weeks, but the mechanic that installed it stated it was a good model and brand. Stated it would do the job on my 1990 Chevy Silverado 5.7L engine with 4 speed trans. The internal cooler in the radiator ruptured and got water in the trans and flat ruined it. So I NEVER want that to happen again so I decided on and external one for my truck. I trust my mechanic and believe this will keep it cool and will NOT have another episode of water in the trans. Stated it was fairly easy to install and fit on the A/C cooler using the supplied hardware. Fits snug and so far so good. If you are looking for a external trans cooler I will recommend this one as my mechanic gave it a Thumbs Up..

I use this cooler on a 2005 Ford Taurus with the AX4N/4F50N transmission. Might be a bit overkill for a car but I'd rather have too much cooling than not enough since heat is an issue with these transmissions typically. At first I found out that I installed it backwards by mistake meaning that instead of the fluid flowing through the radiator then this cooler, the fluid flows through the cooler first then the radiator. I decided to leave it that way due to it not overheating anyway in the summer but was worried about it being too cold running in the winter. The temperatures with it set up that way top out at about 186 degrees F and minimum during the winter is around 130-140 degrees F. It also depends on if you're running the A/C compressor because that will turn the radiator fans on and cool the fluid as well since I have it mounted to the Radiator/Condenser on the lower right side of the vehicle. I noticed no difference with A/C performance with it partially obstructing the condenser and no leaks in three years so far.

Just enough cooler for my Acura MDX with the stock cooler bypassed. Made some aluminum brackets to keep the cooler off the AC condenser. aftermarket temp sensor peaks at 65C in Heavy FL traffic.If I had to do it again I would have went one size larger 679 just for a little extra insurance.Update: 7/11/2017No fan, 100 degree day in stop and go FL traffic temp sensor hit 82C not towing, flat terrain, and AC ON of course. that's 180F and within 10 degrees F of the fluid limits of most transmissions. Next vehicle I will definitely go larger or possibly add a fan to this cooler.Update2: 9/26/2017added a "9" Inch Electric Radiator Cooling Fan 12 Volt Adjustable Thermostat Control Kit" before towing on a 2500 mile round trip from FL through OH for a week and back through GA. First, a 9" fan is too large for this cooler. Suggest a 6-7". The thermostat kit was set to 60C/140F using my aftermarket digital temp sensor on the trans output line BEFORE the cooler. Towing a single axle open trailer with an UTV on it totaling 2000 lbs. Highway temps in 96F FL/GA trans fluid temp 67C/152 using D4 on the transmission. First big 10 mile hill on I77 in VA heading north 62F outside temp with trans temp of 87C/188F. Later in the same day; outside temp 80F, stuck behind a tractor trailer at 40 mph, up a steep 1 mile hill, 2 lane road I hit a max trans temp of 101C/213F. Most consider this to exceed the max temp of transmission fluid and require a full fluid change.Next year I will be reviewing the 679 version. This cooler is not quite up to the task for summer hilly towing even with a fan.update3: 7/10/2020: Lost the cheesy knob for temp control even though I glued it on. I had it set already where I was happy and still hear the aux fan turning on from time to time. the fan I use: American Volt 12V Electric Radiator Cooling Fan

Easy to install if you know how to and what you’re doing. Front needs to come off if you want it to look like this. Make sure you purchase extra transmission line if you want to run it like I did. There are many ways to run a cooler. YouTube before you start and buy the parts you need!!! I also purchased the mounting accessories kit. I dremeled out the metal factory brace so the cooler would fit flush and spray painted everything to match. Used washers for spacing so it was flush. Drilled out the plastic on the bottom to run the lines through. My Tahoe didn’t come with a factory external cooler. If yours did it will be a lot easier.

OK, so I have a 99 Jeep XJ. I dont trust the zips thru the condenser and radiator. I read too many posts on forums saying they ended up with radiator leaks down the road. and some with no more AC. I bought the Hayden bracket kit. I ended up mounting it on the driver side. flipped around so the brackets are closer to the bumper. There are 2 holes that are just behind the bumper than work for mounting, they're a bit tricky but some stuby wrenches and small socket got it done. I stuck 2 of those foam pads to the cooler to pad between the cooler and condenser. And then used 2 of those zips to go above the radiator to keep tension on, I keep the other 2 extra zips in the glove compartment. It took me forever to find a way to mount this thing without pulling the bumper or header panel. I read some people put it in front of the mechanical fan, but my Jeep has 125k and in the morning or when the engine is cold, the tranny doesnt like shifting until its has warmed up. So I figured in front of the electric fan is good compromise. After I mounted it, the rest of the install took literally less than 10 minutes. Its not the prettiest job, but not having to risk my radiator or remove bumper/header panel, makes it worth it to me. Also, if you want consider painting the bracket and nut and bolt before install.Also, the kit came with 11/32" tubing instead of 3/8th. Maybe that is fine, but I ended up ordering Deraile 3/8" transmission hose from Amazon. As my Jeep uses 3/8, so I see no reason to change it. It was fine and works. You also need 3/8" barb connectors and 6 hose clamps total. also doesnt hurt to have a zip tie to tie the hose along the body where you can. I bought mine from Home Depot, but Amazon and Autozone both have it.