Through the dipstick tube
Same place the dipstick is. Use a long skinny funnel.
In the transmission.
Down same tube that holds trans dipstick.
remove the transmission dipstick and use a long nose funnel and with the vehicle running in idle add atf (automatic transmission fluid) to the vehicle
For autos generally thru dipstick tube if says add.
Put a small funel in the spout where you remove the transmission dipstick and pour slowly
lost soulwhat kind of transmission fluid is used in 1998 Hyundai elantra,and where do you put the fluid
Through dipstick tube.
In the transmission.
if its an automatic you put it in through the filler tube or trans dipstick tube if manual on the side of the transmission
The trick is not where to fill it but how to know when it is full. It is best to take it to a garage because it needs to be raised level on a lift.