A Different Transmission temperature question

[karma]

So, I keep hearing that optimal temperature for 5R110 strapped behind 6.0 is 170F - 180F here and the trucks folk. And I understand the transmission is good for 230F or 240F for a short burst. The trucks have big cooler compared to vans and the 2007+ Van grill doesn't help it much with the big Ford logo blocking the air flow. I know people use Trucool and other big coolers to lower temps.

All the above has been discussed, but my question is shouldn't the optimal temperature of transmission be around or a little less than optimal coolant temperature? I say this because the transmission fluid also exchanges heat with coolant in radiator which is typically 200F - 205F normal operating condition? And since the coolant is at higher temp. the transmission oil temp would always be around coolant temperature, the way Ford designed it. So shouldn't that be the normal operating temp of transmission instead?

Thanks

[86Scotty]

That’s always been my understanding, yes.

I think they can handle higher than bursts of 240 too. I’ve heard up to 275 in racing vehicles but I wouldn’t leave it there long.

[carringb]

Only the coolant in the top of the radiator is that hot. And only when the T-stat us open. The bottom of the radiator, where the in-tank fluid cooler is, is far cooler.