Thread: Coolant coming out of transmission line bung in radiator?

I have an 05 GTP Comp G. I pulled it into the garage to change an Oxygen sensor, and discovered a small puddle of ATF on the floor. A quick inspection revealed that one of the transmission lines was leaking near the transmission. It's the line that extends across the car to the lower passenger side of the radiator. I removed that line, and aside from a few more drops of ATF, all seemed well. Today when I attempted to install the new line, depressing the bung that this line threads into caused a bunch of coolant to drain from that opening.

I think the answer is obvious, but I want to ask anyway... did removing this transmission line somehow cause internal damage to the radiator? All I did was unscrew the damned thing!

I unbolted the fitting that the transmission line sits in because I couldn't get the line to come out of it under the car. How does that bolt seal coolant off if that's where the ATF is supposed to transfer through?

yeah, but for some reason the bolt was damaged and was preventing the line from coming out of it, so I had to pull the bolt out of the radiator and do it on the bench. Even on the bench, that bolt was boogered up enough that it wound up breaking the thin end of the bolt past the hole that the clip goes into. I'm just relieved to hear that it's normal for coolant to come out of that hole with the nut removed. I still don't understand why, but I'm ok with that.

Thanks for your help. If I didn't get it, I probably would have wound up replacing the radiator.

Ok, I'm finally getting this thing back together. I picked up the correct bung with the large flange on it, installed it into the radiator, and then clicked the trans line into the radiator. Is there any chance that coolant could have gotten into the transmission cooling line? Should I disconnect the two lines at the transmission and blow them out?