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Help required to find out radiator transmission tube size
So i had a very slow tranny oil dripping ( more like sweating under the lower radiator ) and when was trying to figure out the exact source I noticed the little metal tube under the radiator ( I believe it is the transmission fluid return cooling line ) is cracked and when I tried to waggle it to check further, it of course completely broke off and tranny fluid started to leak . I removed the tube fitting and plugged it , also plugged the return hose , then after some research installed a hayden 678 cooler independently . Now I'm not feeling too confident to drive the car as the weather is heating up and want to go back to stock cooler. But can't figure out the metal tubing which fits in the radiator . So my sincere appreciation if someone can tell me the exact size ( AN or ght or Npt ) .
my car is Maxima 2008
PS : the tube fitting exactly looked like the one in the photo attached
Last edited by mustang86; Mar 19, 2022 at 07:49 PM.
It's an odd leak. I put in a new radiator very recently. In the process I lost about a quart of transmission fluid. When I first put the radiator on, it did not exhibit this leak. I put in some lucas transmission fix because the fluid is worn (I'm going to change it this summer) till the dip stick read full. Now it's leaking out of I believe the lower cooler line port on the radiator.
it is indeed. It was pretty warm here today in new york ( 95f ) and a perfect opportunity to find out if the transmission is over heating. Drove to long island to a far away beach .. to and from almost 150 miles and nope the engine , nor the transmission appear to be overheating and basically functioning properly, smooth acceleration and 65 miles @2200 ~2300 rpm give or take. So the aftermarket active or independent cooler doing the job well.
the reason why I didn't buy a new rad is practically I feel like it is not worth to buy an aftermarket rad only for the transmission cooling coupler damage wheres the rad itself has no leak. And there are always a chance for the coolant get mixed up with the transmission fluid and completely destroy the engine and transmission if I don't buy the original rad.
so I recommend you to check foe hose fitting properly and tighten the still hose ring correctly. If it is coming from the radiator end , try to undersize the hose and re fit . It should be snug. Always make sure you buy the hose specifically designed for fluid/oil and and can withstand high pressure.
I don't know how or even Lucas cvt fix would work but better flush the fluid and get cvt ns 2 fluid or whichever applied for your car model refilled . If still leaking from rad, I would recommend a bypass and install a hyden cooler for transmission.
It's an odd leak. I put in a new radiator very recently. In the process I lost about a quart of transmission fluid. When I first put the radiator on, it did not exhibit this leak. I put in some lucas transmission fix because the fluid is worn
(I'm going to change it this summer) till the dip stick read full. Now it's leaking out of I believe the lower cooler line port on the radiator.
Last edited by mabsarer22; Mar 15, 2025 at 05:43 AM.
