The sudden stench of warm sweet coolant brings plenty of troublesome thoughts to a Subaru owner… Mostly dreaded fears of head gasket failures. But in reality there are countless other areas where your Subaru might decide to spill coolant from.. the biggest area of coolant being the radiator.

Like a bouncer at the club… It’s is your time to go radiator!

The Subaru radiator design is much like others with plastic upper and lower end tanks that are clamped in by the aluminum center section. With enough heat cycles it’s possible for the aluminum and plastic section to go their separate ways… releasing the once contained coolant to the everywhere it shouldn’t be. Like the ground exhaust and the hidden nooks of the engine, so you can always remember that sad moment when your radiator decided to call it quits.

So how difficult is it to change out your Subaru radiator… Let’s go ahead and find out!

Time Frame

The most time consuming part of this project is watching the coolant drain from the petcock…. or you can be a wild man and pull a coolant hose and let it rain. How fast you can remove your coolant generally dictates how long it takes. I would recommend around an hour and half to complete this with a burped coolant system that is ready to roll out.

Tools

Your typical Subaru sockets will be necessary mostly an 8, 10, 12 mm, along with your favorite ratchet or electric ratchet. Also on our list will be a set of larger pliers. Your favorite flat head screwdriver can come in handy for electrical connections and any plastic clips you need to remove.

Grey Pneumatic 3/8th socket set Grey pnuematic wobble socket set 3/8th Gearwrench ratchet

Milwaukee 3/8ths electric ratchet Milwaukee 3/8ths impact gun

Nothing makes your life easier than a nice coolant funnel bucket for purging that air and filling the cooling system to the tippy top.

Parts

As you figured a new radiator is definitely a needed, but which one. An all aluminum upgrade or a standard version. If you are looking to push your car hard and/or live in high heat area an aluminum upgrade might be worth extra cost. Of course you will need some fresh coolant, I have always had good luck with the standard Subaru coolant. Older Subarus will use green coolant while the later models will use Super blue, check your cars specific needs.

Mishimoto Forester radiator TYC factory style radiator

If you are swapping out the radiator you might as well freshen up those hoses too, for fitment you can’t beat Subaru. While you you are in there I would recommend swapping out that thermostat, with a new thermostat in you won’t have to worry about it later down the road. Mishimoto Forester radiator TYC factory style radiator

Installation

Just like most installs we will start with a cool engine bay and lifted hood. If you have recently driven you need to wait for your radiator cap to be cold to the touch in order not burn yourself. Your coolant is under quite a bit of pressure and also very hot, so take the upmost of care to not hurt yourself or others around you.

Once the car has set for a couple of hours and the cap is cold to the touch you can remove it. I would highly recommend to use a towel and glove just in case.

Our next step will be removing any upper shrouding that covers the upper portion of the radiator. Then you head below the engine to remove the splash shield. This will give you access to the radiator drain, for most late model Subarus this should be located on the passenger side. Make sure you set down your 100 plus drain pans so that the coolant can miss them all and land on the floor.

If you have a air induction piping that covers the radiator you can remove it now.

The drain is located on the passenger side of the radiator. This is the newer style, you may find a small valve that can be loosened by hand. Drop your favorite drain pan and empty the coolant.

With your coolant drained you can now grab your 8 mm or pliers (determined by your clamps) remove all the hose clamps. If access eludes you for the lower hoses, skip to the next step for fan removal. If you find the radiator hoses are stuck you can use your pliers to lightly grip the hose while rotating back and forth to free them. If you are replacing the hoses you can also lightly cut through them breaking the seal.

Next up is the lower hose clamp, ready for removal.

Now on to our overflow tank, it’s either clipped into place or held in with to 10 mm bolts. Next you can locate the two fan electrical connectors and disconnect them. You can now remove the 10 mm screws that hold the fan(s) assembly in, there are usually 3-4. Then the fans can come right out!

Your overflow tank will either snap into place or be bolted in. Go ahead and remove it. Now you can remove the 10 mm bolts that hold the fans in.

Here is where you will find the two bolts on the driver side, remove them and the fan will be ready to be removed

Note: For those of you with automatic transmissions and coolers built into the lower portion of the radiator you will want to remove the clips and hoses. If you have two large bolts you can install them into the hoses to keep them from leaking out precious ATF and making your floor a mess.

If you have an automatic Subaru you will need to locate these cooler lines. These are full of transmission fluid so be ready for it to spill out.

Passenger side transmission cooler line.

Having everything else removed you have the last step which is locating the two 12 mm bolts and radiator upper brackets that hold the radiator in. With those removed you can pull the radiator right out.

You will find two of these brackets that hold the radiator in place on each side. A 12 mm bolt holds them in.

Everything to install your new radiator is in reverse unless you were replacing the thermostat, then go ahead with replacing it. Radiator, brackets, hoses, fans, overflow. Then on to the coolant, this is the time where your coolant funnel comes in so handy. You can easily fill the bucket after installing it on the radiator, then fill the bucket half full. If you haven’t seen any leaks during filling it’s time to start the car! Make sure you are in an open area to allow the car to run with the bucket on it. With the vehicle running it will pull the coolant through the system and push the air out, this will be very visible in the bucket.

New radiator getting comfy in it’s new digs.

You will want to let the fans come which is the good sign that the thermostat has fully opened and the air should be purged from your system for the most part. Turning the car off will allow the coolant flow to cease and the engine should pull down a bit more coolant. Now you can remove your funnel and do a second check for leaks. If you are all dry you can head out for a quick drive to make sure everything is normal and the temp gauge is happy and reading normal.

Purging some air with the good old coolant funnel bucket.

Congratz! You have replaced your radiator with a newer shinier radiator that is ready to take some heat for cool it off for you! Hopefully this radiator lasts you just as long or longer!