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How To: Install A Transmission Cooler

21K views 16 replies 7 participants last post by  xenon2000 
#1 · (Edited)
Now this isn't a horrible involved process and just about anyone with a little know-how can do this.
A transmission cooler is a great idea for towing, driving hard, or anything really. It'll vastly increase the life of your transmission. Heat is one of the most common problems resulting in transmission failures.

Also I have the 2.4l LE5 4Cyl engine with the 4 Speed Automatic Transmission (4T45E)
I would assume it's all pretty much the same, but it may vary with the different engines/trannys out there...
And I have the WAMS tuned TCM, but I'm not sure if that's useful info here.

Total Cost: $72.87 After taxes.

What you'll need.
- A transmission cooler kit - Should come with the cooler, Some hose, clamps, and mounting hardware.
- 7mm Wrench, Socket or Bit Driver
- 10mm Wrench, Socket or Bit Driver
- Flathead screwdriver or panel puller
- Knife or blade for cutting hoses
- 2 Vice Grips or clamps to clamp the hoses.
- A flashlight may be useful.
- Jack and Jack Stand(s)
- 2 3/8" Barbed Pipe Fittings That look like this:



Now first thing I did was remove the Radiator cover and the drivers side headlight.

To remove the radiator cover just remove all of the clips holding the top of the bumper on. And then remove the 4 10mm bolts holding on the rest of the cover, Once loose you should be able to just wiggle out of place, A little hard with the hood latch lever being there but it can be managed, it's not too bad.

After removing the cover there is a little rubber air shield sitting on top of the radiator, Simply pull it up, it just fits over a little slot.



And to remove the headlight you'll just need to remove the 2 7mm bolts and then pull out the light as you may have done.



At this point I jacked up the car and set the front drivers side on a jack stand to give me the most room beneath as possible.

Once up you'll need to remove another 7mm bolt and a couple of panel clips to give yourself some work space. You can remove it all if you want, I just puled way enough to reach my hands up in there to get it all done.
The red arrow points to the space where I got in to get to the lines.



Once you get access to the lines you'll need to clamp the hose at both ends and simply cut in the middle, It's a tight spot so be careful not to cut yourself, I got lucky haha. You'll want to install the transmission cooler AFTER the radiator. So the return line coming from the radiator back to the trans is the lower line. Comes from the bottom of the radiator and is the bottom line going back into the trans.
Below is an image where you can see it clamped on the left with the cut following.
This method results in very little fluid loss. Literally a few drops and that's all.
This is a view looking up from the bottom of the car:



I added my barbed fitting to the aftermarket feed line and clamped it. Then connected to other end of the barb into the hose coming from the radiator. I brought it up to where I wanted the cooler mounted and just cut to fit allowing enough room to turn the hose without kinking it. There was plenty to work with.

Now I went with two smaller coolers instead of one larger one, partially for looks and partially for better airflow into the coolers. Plus they're each in front of their own fan. Here's how I set em up:



Once I got it all mocked up I went and ran the return hose, Cut the length to fit and clamped it to the other end of that line.
Here's a finished shot of the hoses clamped:



And here is a view of one of the hoses running beside the radiator to the first cooler:



And finally a view from above after I finally mounted the coolers. I mounted mine to the A/C condenser using the supplied mounting hardware, Which is basically a few zip ties but they don't loop back, they just have a locking piece that goes on the other side of the condenser.



It seems I didn't mount them perfectly straight but it kind of worked out. Makes it visible and somewhat aggressive looking when seen through the grill



When all is said and done you just need to top off the tranny fluid to make up for the coolers taking up that extra volume. On my particular trans I have to have the car in the air and level. Cycle through all the gears and leave it running in park, then remove an overflow bolt and if nothing comes out then add fluid until it just starts to drip out, and then close everything up and that's it.

I checked with an infrared laser thermometer. And just idling I noticed a 10-12 degree drop between my two trans coolers. So it does make a difference but of course while actually driving you get airflow through the coolers and it cools better. Or if the fans kick on...

Hopefully this helps anyone who is interested in adding a transmission cooler!
Let me know of any questions or tips and I'll be happy to accommodate!

NOTE: Be sure NOT to over-tighten the clamps, If you tighten to the point of no return you can compromise the integrity of the trans hose and eventually cause a leak. Be sure to use 3/8" fittings and tighten the clamps just enough, Not so much to skin off rubber from the hose.
 
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#2 · (Edited)
I drew up some quick diagrams to paint a better picture of Trans fluid flow and cutting the lines and such:

You can tell what is the radiator and trans.
The black lines are steal trans lines
The red lines are stock rubber hoses
And blue indicates fluid flow direction:


And here's it after the cooler install:
Same key as above BUT
The Green is the cooler.
The Brown lines are the after-market hoses.


You can also test the lines, You can start the engine. Put it in drive with the foot on the brake for at least 10 seconds, then back into park and turn it off, and feel both lines. One should be cooler then the other. The cooler one is the one you want to tap into.
You could also remove a line and crank the engine for a second to see which way the fluid flows.
 
#3 ·
Does it put any extra strain on the pumps for the transmission fluid?
 
#5 ·
Not that I'm aware of, from what I gather there should be very minimal pressure loss because the type of coolers I used are a single 3/8" tube that passes through the fins. I also dont think there is any extra strain on the pumps because of that.

I've done a lot of research and can't really find any drawbacks. I don't think my trans notices a difference, except in temps! Haha





Nice, have you had any problems like leaks and such?
Nope! Not a single leak. The transmission is working amazingly. The torque converter engages way more smoothly now, so no matter how I start off it feels great. The shifts are all nice and crisp. Under very light throttle it'll shift through the gears so smoothly I don't even notice it. Only reason I know of it is because I watch my RPMs. And under heavy acceleration it runs through the gears amazingly.

And the best part. It ALWAYS works like this. I read somewhere that the dex 6 fluid responds and works really well at cooler temps. And it shows!

Definitely one of my more favorite mods.
 
#7 ·
I unfortunately can't give exact figures. My obd reader can't pick up trans temp from the pcm. But I did check the coolers with a laser thermometer and saw a 15 degree drop from one cooler to the other just with the car idling in the driveway.
 
#11 ·
I don't unfortunately. I checked my receipt. Wasn't on there. Checked the website and can't even find a trans cooler that's the same dimensions as mine. I've been to napa since and they replaced the area with different merchandise. So my guess is what I got is either discontinued or replaced with something that's slightly different in size or something.

I'd recommend just going to an auto parts store and actually taking a look at the coolers you want to buy. You can get an idea for the size you want to run or see if something looks more appealing or seems better suited for you.

I'd also say pull that plastic radiator cover. There's plenty of room but I found it helps to see just how much you really have to work with.
 
#13 ·
Nice, I figured out that I used two "Light Duty" Transmission coolers, From what I've read online one light duty should be plenty for our cars, But I figure two wouldn't be too bad and I'm also thinking about the long term, since I have plans for my motor :D
 
#16 ·
I did that to ensure the transmission warms up in the winter months. The heat from the coolant in the radiator helps the transmission get hot. Of course I loose a few degrees going through the coolers afterwards but from what I've read around the web its enough to prevent it from running too cold in the winter.

And after driving it all winter long even with single digit temps I had no issue. All I ran into was a delayed shift into over drive if I hopped in the car and went driving before letting it warm up for a few minutes. But once it reaches operating temp it worked flawlessly.
 
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