Can anyone identify this part

2004 Dodge Grand Caravan. I’m underneath, center, right around where front tires are. Top of head pointed toward rear, feet sticking out front of car.

The small metal pipe running right to left, has a light brownish/amber clamp on right side and a pile of JB weld goo on top.

It’s leaking coolant and water out of a small hole so it connects to the radiator and cooling system. But it’s not a hose, it’s some type of pipe.
It also has a square piece of metal coming off it to secure it to car I guess.
I want to try to get a new one.


My guess is a transmission cooler line. You have an automatic transmission, right?

That might be a coolant line to the heater core.

It can’t be a transmission line because if it were, it would be leaking transmission fluid instead of coolant.


Yes it’s automatic. When I put water in the radiator it starts coming out of that pipe immediately.

some sort of coolant by pass

Tester is correct, it wouldn’t be the transmission cooler line b/c there’s no coolant in that. Or at least there shouldn’t be. Are you able to determine to what that line connects on each end? My Corolla has something similar to that, and its part of the water pump inlet routing I think, associated with what is called a “bypass thermostat”. But on my Corolla it is nearer to the top of the engine than what appears you have photo’d, which looks near the bottom of the engine.

That is the heater return tube, it connects to the back of the water pump. #5 on the bottom right engine in the diagram (3.3/3.8L).

Wow, thanks.

I just wanted to thank you for posting those great photos accompanied by that great description. I truly wish more posters would go to the trouble you did to give us good, solid information.

I tip my hat to you. Sincere best.

Thanks. This site really helped me move forward on repairs!

I agree with mountainbike. Most posts would have been “My car is leaking. What is it and how much will it cost to fix?” leaving the readers to know as little after reading the post as they knew before starting.