I would think the tranny was either overfilled, or the temp was over 200 degrees. I experienced this with a stock tranny, but had an autometer temp guage. Mine puked out fluid from the overflow at 210 degrees. I only had a MagHytec pan on the tranny, no additional cooler. It took awile to cool the tranny. The mechanic that is telling You need all this stuff, I think He is trying to empty Your wallet. I would suggest a good tranny cooler, a trucool max, or the 6.0 cooler. The tru cool max is about $140.00, the 6.0 around $300.00. I am not a fan of deeper tranny pans, all it does is hold more fluid.