I have always heard after radiator, and that's how I installed mine. I just pulled loose the rubber hoses where they go from tranny to front end of van. It's no big deal to just start the van for a second to see which is return. If I was at home I could run out and check, but I am at work. I put my tranny cooler on at 18,000 after I bought my 96 van, I have changed it every 20-25,000 miles with mobil1 or aamco semi-synthetic. Its still going at 135,000.