2002 HONDA CIVIC LX SEDAN

It’s either going to be 8 or 10 mm and the auto parts store is going to offer you either 5/16″ or 3/8″ ID hose which would work just fine in either case. The OE replacements from the dealer aren’t very unreasonable if you’d rather just get the exact fit hoses. You’ve got two options for the longer of the two. It’ll be between you and your local Honda dealer to figure out which of the two is right for your car. The two labeled callout 11 at least each have their own part numbers. The shorter hose of the two seems like a no brainer to buy no matter what.

I don’t have an answer as to which is the inlet or outlet. However, I don’t see a reason why it needs to be in one hose or the other. It’s just fluid passing through plumbing. You probably do have to worry if the filter has a direction of flow. I’d suggest this; just disconnect one of those transmission hoses from the radiator, connect an alternate hose to the radiator fitting, and set both hoses into a drain pan. Run the car briefly to see which hose is pushing out transmission fluid. (You can have a friend help out on this one. The ATF won’t flow so strong so you can do this without any harm or making too much of a mess.) That will tell you which direction the fluid is flowing in. Then set up your inline filter accordingly and top off the transmission fluid as needed with new ATF.