aftermarket transmission oil cooler

[thamesc180k]

hi all, im thinking about removing the pipes to the trans oil cooler inside the radiator and fitting an aftermarket cooler.
my 04 w203 m271 is supposed to have issues with coolant into the trans oil and thought this modification would be worth while.
i have an inkling that the radiator has been changed before my ownership but no way of confirming this, and adding an external cooler would ease my mind.
Any info on whether im wasting my time and why (car is 20 odd yrs old with 167xxxkms) would be appreciated.
How do i find a suitable one? i cant see whats inside the radiator so sizing is difficult.
Thanks Karl

 

[Gollom]

hi all, im thinking about removing the pipes to the trans oil cooler inside the radiator and fitting an aftermarket cooler.
my 04 w203 m271 is supposed to have issues with coolant into the trans oil and thought this modification would be worth while.
i have an inkling that the radiator has been changed before my ownership but no way of confirming this, and adding an external cooler would ease my mind.
Any info on whether im wasting my time and why (car is 20 odd yrs old with 167xxxkms) would be appreciated.
How do i find a suitable one? i cant see whats inside the radiator so sizing is difficult.
Thanks Karl

The easiest way to tell the Valeo radiator from the BEHR radiator is to look at the top right corner (when youre standing facing the car with the hood open). If you see a little protrusion (welding seal), you have a BEHR. If you dont, you have a valeo.

 

[Bellow]

Bear in mind that the original saddle cooler will, when the engine coolant temp is above ATF temp, warm the ATF. Cooling of the ATF only occurs when its temp is greater than the coolant's. A separate cooler dispenses with all of that and without a thermostat (there may be one in the gearbox but I doubt that there is) the ATF will likely be running too cold most of the time.
I run a separate cooler (original OEM fitment as an addition to the saddle cooler) but without the saddle cooler but I installed a thermostat to avoid overcooling the ATF. I suggest you do the same if fitting a separate cooler.
If, your original rad is OK and unlikely to leak - I'd leave the system as it is.