Thread: Trans cooler install on 07 GT

Okay, I have been thinking of installing a trans cooler for a long time now. I ordered my header panel to replace the damaged one from where I hit a deer a few weeks back. I figured since I have to remove the bumper cover to replace the header panel, I may as well look into adding a cooler while the bumper cover was off. Also since I will be doing the cooler, and I don't know the last time the trans fluid was changed I figured I would do a pan drop and fluid change.

My questions are the following:

1. Do you think I will have a problem doing the pan drop and fluid/filter change with unknown mileage since the last fluid change? The car has 158,000 miles. The trans doesn't slip, but the fluid looks dark red.

2. If the fluid change is going to be okay, should 2 gallons (8 quarts) of Dex/Merc Valvoline Max Life be okay? It says it is compatible with Dex VI.

3. Do you think this cooler will be okay? Buy Imperial Plate and Fin Style Trans Cooler 3/4" x 9-1/2" x 11" Heavy Duty 243008 at Advance Auto Parts If the link doesn't work go to Advance Auto's website and look at part number 243008. The cooler is 3/4" x 11" x 9 1/2". It comes with rubber hose, clamps, and some mounting hardware.

4. Lastly, I have searched all over the forum and there is not a good write-up anywhere for a trans cooler install. I did find which fitting goes to the cooler, and which is the return to the trans, but did not find anything on how people are actually attaching the hoses to the factory hoses. Anyone got any descriptions, or better yet pictures?


Appreciate any and all input. If I get everything I need in time I will get this done before I make a trip to Norwalk on the 4th for the NHRA Nationals and I will try to take pictures and detail the install.

Pan drop and fluid change will be fine. Add a bottle of lucas to it. 2 gallons will be fine. I had a little cooler on my 98 and it worked great.

Any other input?

Decided to go with the Hayden 1404. Got it for $20 cheaper off of eBay than what I was getting the Imperial for from Advance, and the size is a wash between the two. Install will be on Friday or Saturday.

im going to be doing a pan drop and fluid change here soon too im just gona do the VI and let it be.

let me know how that trans cooler goes i think i might do one my self

Turbo Greg badass guy pointed me in the direction of a Hayden trans cooler off of Amazon.

Cheap and very effective according to him and other LS4 guys.

Let me know how it works for ya man.

Bio, your link takes me to parts geek and the part listed is actually just the mounting kit.

The Hayden 1404 should be here tomorrow, or hopefully by Friday. I picked up the fluid, the Lucas, and the filter kit today. Weather dependent I will probably see about getting the bumper cover off tomorrow evening, or may put that off until Friday. This is going to kind of suck, because this will be the first work I have done on a car at the current place, and I don't have a garage. I really don't even have a real driveway.

Send a message to marines542. I think he's got two coolers run on his car, or about to... He got one from TEP and bypassing his radiator cooler. He might can shed light.

I've been watching his posts as I know about his potential install.

This is not like its a difficult job at hand, I just was looking to see if there were any install tips or tricks to look out for.

Honestly, I think my biggest hurdle will be getting the bumper cover off without getting pissed off and damaging something.

I used the Valvoline dex/merc (not maxlife though) and it said compatible with dex III. So not compatible with 2006+ Check yours again.


The 404 is a somewhat big cooler for a N/A but will work fine when mounted horizontally on the condenser. It's taller than the space vertically. I used the 403, and it's the largest size that fits vertically.

I know you saw my post on the other thread, but for reference: You can tap into the stock lines by cutting the hoses, and buying a double male coupler for 3/8ths hose, or you can cut the metal lines after the hoses and slide the hoses on there.

Are you planning on running the cooler independent or in series with the stock rad cooler? I did independent for a few reasons, one being no chances of the rad failing and sending coolant in the trans

When I do mine I'm going to use a large one, with a fan... I'll do independent also, just to keep the fluid away from hot coolant. My winters here are mild so no need to help "warm up" my fluid..

I plan on running independent. Also remember the 07 GT is supercharged.

As for the ATF according to the description on Advance Auto's website for the Dex/Merc

MaxLife DEX/MERC ATF contains a blend of base oils and a unique additive package to help extend the life of transmissions with over 75,000 miles. It is formulated to maximize transmission performance, reduce transmission wear and improve and maintain smooth shifting longer than conventional fluids. MaxLife DEX/MERC ATF is compatible with new and rebuilt transmissions and will not void new car warranties. Recommended for use where DEXRON, DEXRON II, III and VI, Toyota T-IV and WS, MERCON®, MERCON® SP and LV, Allison TES 295 and 389, Nissan Matic-D, Matic-J and Matic-K, Honda Z-1 (except CVT), Mercedes NAG-1, Mitsubishi Diamond SP-II and SP-III and many others are required.

I'll figure out what work's best for the lines. If I decide using a male/male coupler is better then I will cut further back on the stock lines, and just have to run to the hardware store and grab the fittings.

Its as simple as cutting the factory lines where there rubber use a double barbed Fitting to connect them. Skip the Lucas and honestly I wouldn't buy the vqlvoline is any better than any other brand of dex 6 . in also running the 1404 cooler. Bumper is to easy remove 4x10mm bolts on both sides where the fender and bumper meet. Remove the 6-8 7.5mm bolts that attaches the bumper to the underbody cladding. The. Remove the plastic push pins

When I did mine I just cut the lines where they connect to the radiator left it a straight cut no flare or anything and ran hose up to the cooler.

Now I know why there is no write up or how to on installing a trans cooler.

After taking the front bumper cover loose to change the header panel I started looking closer and realized I had to remove a ton of sh!t just to mount it and to get to the lines. Then I saw no real clean way to route to lines. The instructions say its a 30 minute install.... it would be more like a 2-3 hour job, and that's if everything goes right.

After looking at all of that I said F$CK it. I am not going to go through the hassle of installing a cooler on a car that doesn't get raced.

I will probably just sell the damn cooler now so if anyone is interested keep an eye out for a sale post.

Take a deep breath exhale.....now look where your driver side wheel is where the subframe bolts to the body you run your limes through there around to the cooler

Again, there is not real clean way to run the lines. There is a way, but not the way I want to it to be done without drilling or cutting.

As it was, I was at my uncle's house using his garage to work on the car, and I had him take a peek at it to see if I was overlooking a simple route and he 100% agreed with my take on things.

Originally Posted by stealthee

Again, there is not real clean way to run the lines. There is a way, but not the way I want to it to be done without drilling or cutting.

As it was, I was at my uncle's house using his garage to work on the car, and I had him take a peek at it to see if I was overlooking a simple route and he 100% agreed with my take on things.

no cutting




NO kinks or sharp bends and nothing to possibly tear the lines on. Dont know how with the bumper off you guys couldnt get it.