How do you check oil level of automatic gearbox?

To check the oil level of an automatic gearbox, first ensure the vehicle is on a level surface and the engine is running at idle. Locate the transmission dipstick, usually marked with a bright handle, and remove it. Wipe the dipstick clean, reinsert it fully, and then remove it again to check the oil level against the marked indicators; the fluid should be within the designated range. If necessary, add the appropriate type of Transmission Fluid through the dipstick tube, and repeat the check to ensure the correct level.