Offroadmuch
Explorer
Quick diy guide time!
Coolant tee replacement (tees only if you have a rear hvac unit, otherwise you may have a straight coupler or nothing at all).
Tools needed: pliers, screw driver (or suitable tool for worm gears), large container to catch coolant, funnel.
Parts needed: 2 or 3 gallons of coolant, 6 Hose clamps (worm gear style). 2 replacement tee fittings. Brass fittings will work, but if your coolant isn't in good shape, you risk galvanic corrosion in the coolant passageways. Aluminum and plastic are the way to go. Fittings are 5/8". I picked these up off of EBay for $10/pair.
First up, make sure your engine and coolant is at ambient temperature.
Grab your large plastic container and pliers. From the passenger side of the car, just behind the passenger front tire- slide the container under the car behind the front passenger wheel.
With pliers in hand (and some towels to clean up), lay down next to the car with your head towards the front tire. I had to partially slide under the car to have enough room to work. A pad or some cardboard would be good to lie down on. You will find the heater core hoses just behind the passenger side tire, between the engine and the passenger side frame rail.
The assembly of hoses looks rather complicated, but it's fairly simple. Just think of the system as a feed side and return side. The system tees (splits) for each heater core, and the task is to just swap one part at a time. Use the pliers and loosen all factory clamps. Then just pry the hose from the coupler away from you if possible. Coolant will of course be rushing out, so plan to allow it to drop into the large container.
Coolant will stop in a minute or two. Completely remove the single tee and then the hose clamps. I urge you to replace the hose clamps as the OEM ones may not be so elastic anymore and you may get leaks after the install. Assembly is the reverse steps. Just place the new hose clamps on the hose, then install the new tee. Set the new clamps in place and tighten. Repeat for the other tee, noting that there will again be coolant in the other side.
Remove everything from underneath the car and fill radiator until full. Once full, turn engine on. Its ok to have the cap off still. Crank your hvac controls to maximum heat and return to check coolant levels. You have a few min to bleed the system before it gets hot. I tend to 'burp' the system by grabbing onto one of the two radiator hoses and gently but firmly squeezing. Cap the radiator.
That's it!
Just did this exact same job with the same aluminum T's I ordered from the link. Just a few words caution or advice I would offer:
The two ends of the T that are in a straight line (the top of the T) are the exact same size as the orginal plastic. The other leg of the T is smaller on the original plastic T by about 1/16th so when using the aluminum you will find that it is extremely tight to get the new piece in place. I sanded down the aluminum pipe where it goes into the slightly ly smaller line and it was much easier. Also, the plastic was very brittle and crumbled with finger pressure. Be careful not to get these sharp plastic particles in your coolant lines. I had to dig out the broken ends of the old plastic T's from the rubber hoses. I used about 1 full jug of coolant plus about another quart. Finally, if you have skid plates your coolant lines should be protected and the delicate plastic T's should not be an issue however one of mine was so brittle I am glad it is off my truck and I do have better peace of mind.
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