XJ trans. cooler lines...

Long story short, I decided to flush the trans. today by cutting the soft trans. cooler return line and draining it into a bucket. I had a my friends wife put it in drive while he poured in new fluid, and I held the line in the bucket until it was nice and red. All went great until I tried to splice the soft line back together. I went to home depot and picked up a 3/8" and 1/2" hose coupler (barbs on both ends). The 3/8" coupler was too small and the 1/2" coupler was way too big. I wrapped a few raps of tape around the 3/8" coupler to make it fit snug. After that I tightened both ends down with hose clamps. I didn't even make one lap around around the block and it spit the coupler out and blew ATF everywhere! What do I do now? I thought about replacing the entire factory soft line but it is held on with some special looking metal doo-hickeys at the factory hard lines. Suggestions?

Just an FYI. Neither Newark location Home Depot has anything other than 3/8" or 1/2" barbed hose couplers....period. On a super long shot I stopped by my local parts plus that is typically only good for pissing me off and making me want to snatch the work release cashier across the counter and beat their face in. They however did have exactly what I needed. They sell a "Transmission Cooler Soft Line Repair Kit" that consists of the barbed house coupler in the size that you need with two hose clamps. Ten minutes after I got home it was golden. Shifts like dream now, what a difference it makes when the transmission has ATF in lieu of muddy water.