Unlike many vehicles, the 2003 Honda Odyssey requires owners to add transmission fluid while the engine is cold. It’s important to make sure that the van is parked on an even surface and in park before attempting to check or add transmission fluid. The transmission fluid keeps your transmission lubricated so that your vehicle can shift gears properly and prolongs the life of the transmission. You should check the fluid frequently and add to it as needed.
Open the hood of your Odyssey.
Remove the transmission dipstick from the fill hole. Wipe it off with a rag and reinsert it in the fill hole.