got water leaking from what looks like the rear of motor. looks like the water is leaking from the transmission

It very well could be coming out of the rear seal of the intake manifold. If it's coming out that fast, check the fittings, hoses, clamps at the heater core where it enters the firewall. It could be dripping down the firewall and onto the trans.

Sounds like a hose broke and the water is running down the engine making it appear as though that's where it's coming out. A very slim chance is on some 4 cylinder engines ... that's where the thermostat is . but the odds of that getting damaged are minimal