Keeping things "cool" with an Auto Transmission Cooler

Wholesale Automatics External Transmission Oil Cooler

If you have a Ford Ranger PX1 or PX2 Automatic, a Transmission Cooler should be added onto your list of modifications. Especially if you are towing heavy loads regularly or if you carry around a lot of extra weight on a daily basis. Also if you are running larger tyres and putting your car through it's paces on the tracks of a weekend, I believe you could still benefit with this upgrade. It's worth having that extra piece of mind that your Auto is running as cool as possible.

It is well known that the PX1 and PX2 Ranger Autos are prone to over heating, some what of a flaw with Ford's design. There is a heat exchanger fitted to the side of the transmission and its job is to cool the transmission oil using coolant from the radiator. Basically it is using hot coolant to try and cool even hotter oil. The transmission temp usually hovers around 100'C with normal everyday running but can increase rapidly under heavy load. Something I found out when towing my off-road van up a steep hill in The Watagans National Park. Before I knew it the temperature of the Transmission Fluid had climbed to 125'C at which point I stopped to let things cool down. Had I not installed a Scan Guage II I would not of known to stop and give things a rest which could of ended badly.

It is recommended that the Transmission Temperature not exceed 125'C. Exceeding this can cause the internals of the heat exchanger to fail, which will cause coolant to mix in with the transmission oil and then next thing you know your parked up on the side of the road waiting for a tow truck.

Installing an external transmission oil cooler kit allows the oil to be cooled by using the cooler air at the front of the vehicle, keeping temperatures in a better operating range. The radiator coolant bypasses the transmission and separates the cooling systems of the engine and the transmission.

I purchased my cooler kit from Wholesale Automatic Transmissions, It includes -

- 1 Dual cross cooler mounted to a bracket

- 1 J-Pipe radiator hose

- 5m hose with conduit

- Dual cooler connection hose

- 2 custom cooler unions with O-rings

- 1 M6 Bolt and 2 self tapping screws

- 6 x 8-16 screw clamps and 2 x 14-27 screw clamps

Step 1 - The first step of in the install is to remove the front grill assembly which will allow access to mount the cooler in position.

Step 2 - Before mounting the cooler in position using the supplied bracket and fixings you must install the hoses to the cooler itself. The short hose links the 2 coolers together and the longer 5m hose will be looped around, this will be cut into two seperate lines later in the install. Installing the hoses at this stage will make things easier as there is not a lot of room to fix them from underneath once the cooler is in place.

In my case, I have a TJM T13 Bull bar and a Dominator Winch housed inside the bar. I had to undo the winch from its mounting position to allow me to slide the cooler bracket into place. It was a tight fit along side the winch but it all worked out eventually. Different bars and winches could have more room, or less room than what I did but just something to keep in mind with your install.

Step 3 - Once the cooler is mounted in place you will need to run the looped hose towards the heat exchanger on the passenger side of the transmission. Zip tying along the way.

Step 4 - Time to remove the heat exchanger. To access the heat exchanger you will need to un bolt your front drive shaft to give yourself as much room as possible to work with, unless you are extremely flexible and have tiny hands I suppose. Once you've un bolted the driveshaft zip tie it to your chassis rail to keep it out of the way. Two radiator hoses that run into the heat exchanger need to be disconnected. Clamping these 2 hoses before removing will save you having to replace coolant at the end of the install. I attempted to clamp the first hose when removing but it did not go to plan. I drained the coolant into a bucket to reuse later on. With hoses removed you need to undo the 3 bolts which hold the heat exchanger in place and then it can be pulled out.

Step 5 - Fit the supplied J-Pipe to the radiator hoses so they link together allowing them to bypass the transmission.

Step 6 - Fit the custom unions to the side of the transmission by re-using a bracket from the removed heat exchanger. It is easiest to cut the hooped hose and clamp them to the unions before fitting to the transmission. Be sure to allow some extra slack in the hose lengths when cutting, this will allow for a bit of movement when your travelling along some bumpy terrain.

Step 7 - Check all hoses and fittings are tightened and firmly in place, re-fit the front grill and any bash plates underneath that may have been removed. Top up coolant if you drained the system in the earlier steps. Top up transmission oil, this was a bit of a pain to do but made easier with a couple of funnels and a length of hose.

If your reasonably handy on the tools then there is no reason why you can't install this kit yourself. If I managed to do it then you can too. The Wholesale Automatics kit comes with a decent set of instructions to help you through the process.

Early thoughts on the cooler are great, the Automatic Transmission is running around 10'C cooler than it used to (90'C). Only having tested it on road so far and also yet to hook the Caravan up to really test it out. Also noticing the engine coolant temp to be running slightly cooler also now that the 2 systems are working independently of one another.

I can feel a little more at ease now knowing my Automatic Transmission is less prone to any over heating issues. If you own a PX1 or PX2 Ford Ranger I would highly suggest installing one of these kits.

Check out the link below if your interested in grabbing yourself one.

https://automatictransmission.com.au/shop/dual-external-transmission-oil-cooler-kit-to-suit-ford-ranger-6-speed-auto/

Thanks for reading. If you have any other questions send me a message or leave a comment below!

Josh