Cruising down I95 at 75mph last night next thing I know its like the car is in neutral, I got nothing for a trans. Coasted to a stop and left the car. Towed it home today and investigated, fluid leaked everywhere... the whole bottom of the car back to the mufflers is wet.

Somehow a trans line that goes to the passenger side of the radiator busted, and my car not only puked out all the trans fluid, but it also puked out all of the coolant. I can only see the obvious damage to the fitting on the radiator but I am completely stumped on how I lost all of the coolant too.

Has this fitting ever broken off on anyone else in here? Any clues?

 

Most likely someone over tighten the trans cooler line fitting and cause a fracture in the plastic coolant tank. Over time the fracture traveled around the fitting due to vibration/contraction/expansion/etc. It's no accident that it broke right at the fitting.

The coolant came out when the fitting broke. The fitting is connected to the trans cooler which is inside the black plastic tank and is submerged in coolant. When the fitting broke it took a chunk of the coolant tank with it. In other words it put a hole in the coolant tank.

Plastic tanks are usually held in place by crimping on to the aluminum radiator tubing/fins and sealed with an O-ring. The tanks are attached on the ends of the tubing. Depending on the manufacture they may be top and bottom or side to side. Metal tanks are soldered on to the metal tubing.

 

So you think it was overtightened from the factory? This line has never been removed and the replacement radiator i ordered comes with the fittings already installed.

One thing i did notice is this aluminum fitting has steel washers, and they broke in half when i touched them because they were rusted out, i wonder how much that contributed to this issue.

Thanks for the reply

 

Also i think the trans fluid runs through the bottom of the radiator to warm it up faster honestly, the TLS has an external cooler in the drivers bumper area already. Idk either way im assuming this doesnt happen very often, which is typical of my luck.

 

The additional cooler seems odd to me. That's additional baggage for them to deal with. More parts, money, assembly time, additional parts that can fail. Apparently the trans is quite tempurature sensitive. Maybe they wanted to increase the volume of the fluild or both volume and optimise tempurature.

 

thats the power steering cooler not for the trans, the one you see on the front bumper on drivers area

 

Oh ok so the power steering cooler is the square cooler in the corner of the drivers bumper? Gotcha

 

I went to swap my snow tires today, and the dealer alerted me that the fitting was corroded and that radiator replacement was in order to avoid what happened to OP. I asked to see it and in fact the nut was completely corroded. Here in Toronto, Canada the dealer charges $628 + tax to for the work. I was going to wait until I am at the dealer again in late April to swap my all seasons, but it seems like it's a very risky decision considering what happens to the transmission when the fitting breaks. Granted I don't drive my car much (just over 3k miles a year), but the risk is making very nervous right now.

 

Do not bother buying from the dealer, the radiator is not a Honda part, it is made by Denso. I bought the exact idential Denso core from Rockauto for like $120 and it really isnt that hard to install, took me maybe 30min... save yourself a lot of money.