I think I installed the Ford Racing cooler. After a day at the track I notice the transaxle has signs of oil around the breather, that's just my 2 cents.
I, too, had this experience - although it may have been caused by the improper assembly of the breather to the transaxle at Ford's assembly line. Long after installing the Ford Racing cooler, upon disassembly, I found that a flat washer was placed between the transaxle and the factory breather's O-ring, allowing weepage between the transaxle housing and the flat washer.. By this time, however, I had purchased the T&A breather, and assembled it properly with an BUNA-N O-ring AN Adapter. I have never seen any weepage at the housing since that time.
I might also state that the OEM breather is only about ¼" above the housing, so that any fumes are much more likely to escape and settle on the housing due to the close proximity, than with a breather with filter spaced 2 ft. away.
I understand Kendall's point - that no fumes will be present with the cooler in place, however, as I had already bought the breather when I found the flat washer problem, I installed the T&A breather anyway. And, I might add, it looks
sooooo OEM and professional with it's chromed top filter that aesthetically it complements the engine compartment. So does Mr. Guyett's filter, as I have seen from the pictures.
Lastly, I will say that I have never seen any weepage at the top of the transaxle with both the Ford Racing (OEM) cooler and the T&A breather in place. It may be overkill, but it sure looks good and performs flawlessly