The manual says there are multiple flavors of ZF8hp in our defender: 76, 70 and 45 and they are all listed as in those with I4 /2.0L gas engine(!). Considering there are also I6 and V8, I am afraid the matter could be a bit more complicated.

Actually, after checking with an online part source, it turns 45 is for I4 gas, 70 is for I6 gas and 76 is for V8 gas.

The reason I look into this , is to find out where the ATF thermostat is which controls the cooler loop.
I guess I just have too much time at my hand and got nothing better to do. (actually, I am figuring where to tap in to flush the whole thing, instead of just dropping the pan)

But still, will anyone knows better can share some knowledge here?

 

Looking at the parts diagram, it depends on which 8HP version you have. Some appear to be integrated on into the lines, and I imagine others are possibly internal to the transmission housing (likely accessible with the pan dropped).

With that said, it may not be worth the extra effort to flush the lines. The volume of fluid in the lines/cooler is minimal as the cooler is actually a low volume fluid/fluid heat exchanger.

 

The p300 up to model year 23.5 has the 8hp45. 23.5 and up has the 8hp51