does it matter which way ?

mopar410 said

The riseing heat is an aid to help circulation:enters at the bottom and the heat will rise and help push the fluid out the top same as or more used in a radiator.If heat enters the top it will try to work against the flow.But like I said thats in coolant,trans lines probably dont matter as much.

Click to expand...

What radiator in what car have you seen the HOT enter at the bottom and flow up?

Ok lets all think for a moment...

Hot fluid , it expands and it has LOW viscocity flowing FASTER or EASIER , so if anything as it gets cooler it gains back some viscosity becomes HIGH viscocity and flows SLOWER...
however this is being pumped....

If you got air bubbles in your trans you got problems.... and the fluid will show you so by looking aerated.

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