Help Needed - Transmission Cooler Radiator Fittings
I'm referring to the upper and lower transmission hoses that are connected to the right hand side of the radiator.
I have a major leak from the upper fitting from the union that is fitted to the radiator. The leak is not from the thread but from around the female fitting that sits flush with the outer casing of the radiator. When I screw the male fitting back in place just gentle pressure on the thread causes transmission fluid to gush out around the outer edge of the female end that sits flush with the radiator. Currently the only seal to prevent fluid loss is the metal washer fitted to the male fitting.
A few images to explain what I mean.......
Upper and Lower Transmission Cooler Lines
Upper Transmission Cooler Line - 19mm nut and washer
Female connection on the radiator
Transmission fluid leaks from around this edge
So with the male fitting attached and the pipe connected, just pushing on the fitting will cause transmission fluid to leak. I have tightened the 19mm nut as tight as I dare but still have transmission fluid leaking from behind the washer.
Should tightening the male fitting cause the female end to sit tight with the edge of the radiator and create an air tight seal? Or should the female end already have an airtight seal and so my radiator needs replacing?
Would appreciate some advice from anyone with first hand experience before I spend a further £450 with the main dealer?
This is indeed time for a new radiator.
Here are the directions.

thank you.
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I'm referring to the upper and lower transmission hoses that are connected to the right hand side of the radiator.
I have a major leak from the upper fitting from the union that is fitted to the radiator. The leak is not from the thread but from around the female fitting that sits flush with the outer casing of the radiator. When I screw the male fitting back in place just gentle pressure on the thread causes transmission fluid to gush out around the outer edge of the female end that sits flush with the radiator. Currently the only seal to prevent fluid loss is the metal washer fitted to the male fitting.
A few images to explain what I mean.......
Upper and Lower Transmission Cooler Lines
Upper Transmission Cooler Line - 19mm nut and washer
Female connection on the radiator
Transmission fluid leaks from around this edge
So with the male fitting attached and the pipe connected, just pushing on the fitting will cause transmission fluid to leak. I have tightened the 19mm nut as tight as I dare but still have transmission fluid leaking from behind the washer.
Should tightening the male fitting cause the female end to sit tight with the edge of the radiator and create an air tight seal? Or should the female end already have an airtight seal and so my radiator needs replacing?
Would appreciate some advice from anyone with first hand experience before I spend a further £450 with the main dealer?
Thanks in advance!
Once the new radiator is in place and lower cooler line is connected, refill the transmission fluid from top hole before connecting the top line.
A better and more accurate way of filling/checking transmission fluid is to open the transmission drain plug once ATF is reached 45C, to let excessive fluid out or fill if nothing come out.





