I got to agree with Bobb. It depends where you mount the additional cooler.
If it is an early model 92/93, it may have clutch plate debris in the radiator cooler. I would reverse flush the cooler tube, and fit a transmission filter to the trans outlet. The additional cooler is fitted between the filter and the radiator inlet. The outlet of the radiator, goes back to the transmission.
If the additional cooler is mounted after/or instead of, the rad cooler the ATF temp can be too low, for the proper operation of the trans. As Bobb says lock up may not operate, which will cost you in miles/gallon.
It is important that the rad cooler is the last, before the trans. This stabilises the temp and prevents the oil from being cooled too much. The filter must be for an auto trans, an engine filter is too fine and will restrict the oil flow.
Harvey.
