It isn't "required" but it is highly recommended since heat is the transmission killer, and while you have all sorts of bits out of the tranny, what better time to install a cooler if you don't have one already. I was going to install a cooler first fluid change, and that became the J-MOD time too. There is nothing about the JMOD that increases heat or causes a cooler to be required when it didn't need one prior.
97 Mark VIII LSC/Silver/Gray leather
97 Cougar 4.6 Sport/White Opalescent Tricoat Metallic /Gray leather down but not out?
89 Cougar LS 3.8/Oxford White/Gray velour/HG need replaced AGAIN
00 Grand Marquis LS/Vibrant White/Gray velour
63 Falcon 302/black and rust/shed isn't moving
82 F-150/Oxford White/dumb VV carb doesn't pass emissions