I dropped the skid plate on my '98 4runner for an unrelated reason and saw some green coolant dripping from the hose on the bottom passenger corner of the radiator where the hose meets the radiator.

I thought, no problem, I'll go get a new hose. I pull the hose and see pink fluid drain from the line and realize it's transmission fluid. No green coolant came out the radiator, however.

What the hell is going on!? Why is green coolant dripping from the trans line? The car runs perfectly fine.

 

Google: Pink Milkshake 4Runner

Hopefully that's not it but the trans fluid circulates through the rad for cooling. Add a trans cooler and that will avoid the "Pink Milkshake", when trans fluid mixes with coolant.

 

Thanks for the response, ThorInc.

I am googling pink milkshake, and I guess that has to be it. However, my coolant overflow is green and the transmission dipstick looks normal, not milky. Transmission behaves normally. A little problem shifting from reverse, but it has 320K on it, so I think that's just wear and tear.

So I think maybe I have a really small leak and just got lucky? Either way I guess I need a new radiator.

 

If there is no mixing, awesome. Stop the leak and add a trans cooler, flush the rad and change the trans fluid while you are at it. I may not be the pink milkshake but this is a great time to make sure you never do.

 

Thanks for the advice, I think I'll do just that

 

Maybe the leak is somewhere else and just flowing down the hose.
If you removed the hose and antifreeze didn't come out then it can't really be coming from the hose.

 

I can`t work on cooling systems without a pressure tester makes finding small leaks easy most of the time .

Coolant leaking and dripping down on the cooler line.

 

So I dried everything up and waited a day to see what exactly was leaking from where. From the pic below you can see that the nipple for the trans line is dripping red transmission fluid. But the nut that is holding the nipple is dripping green coolant! Not sure what to make of it. Any thoughts?

 

U needa new radiator.

Plastic/aluminum ones are not reliabily repairable.

 

The nipple is dripping (not leaking) transmission fluid because that's what goes through the bottom part of the rad.
It's dripping because you took the hose off. If the rads leaking then you should change it.
I'd do it soon in case it does leak into the transmission cooler part.

 

Right on. Will be replacing the radiator. Thanks

 

In the pic you can see the far right most three crimps are damp and darker. Your rad is leaking somewhere above and coolant is collecting at that fitting as the lowest point.

If your trans dipstick is still clean and red, I don't believe you are suffering a milkshake. More than likely just an old rad that needs to be replaced.