1986 JCB 1400B Backhoe?

Why do the members posting keep confusing water with coolant?
My machine has "water" contaminating my tranny fluid, not coolant and it reoccurs regularly. After 3 filter and fluid changes, the problem persists. My cooler is perfect and I am running antifreeze (coolant) in the Rad so the cooler is not the problem.
My shifter boot is in great shape, the dipstick has the proper gasket and the hood and cab are water tight. Any ideas??