External Transmission cooler?

[teknik_ranger]

Has anyone ever put an external trans cooler on their X? I've got a 2000 X5 with a 4.4l and that 5hp24 trans. 155000 miles on it when the trans failed. Pulled it apart and found that the friction discs were alright (replaced them anyway), but found that all of the o-rings were hard and brittle, and there was a axial needle bearing that failed between the a/b clutch and the c clutch. Fluid was black and smelled burnt. I've owned the X for 7 months and obviously the previous owner didn't maintain it!!!

Nearest I can tell is that the o-rings failed because of heat, which caused the a/b clutch to slip making the bearing overheat and fail. So I'm planning on putting an external cooler (and possibly a external filter) on it but wanted to know your thoughts. Also I'm going to wrap the exhaust since the cat's sit right next to the trans...excess heat sucks.