By Ralph Kalal
If you have a late-model car, it may not have a dipstick for checking the transmission fluid. Not only does this make it difficult to check fluid level and condition, it also eliminates the dipstick tube or opening through that fluid is normally added to an automatic transmission.
Among the makes that equip some of their vehicles with no dipstick automatic transmissions are Acura, Audi, BMW, Cadillac (Catera), Chevrolet (Equinox), Chrysler (300), Ford, Mazda (Miata and MPV), Saturn, Toyota, and Volkswagen. At present, the unifying factor is that the transmissions on these vehicles are all of European design. However, the concept is spreading: the GM built 6-speed automatic used in the latest BMW models also lacks a dipstick.
If the vehicle does not have a dipstick, the transmission fluid must be checked at the transmission. This requires lifting the car on four jack stands; it must be level to check the fluid. There will be a fill plug on the side of the transmission case. This is not the drain plug located at the bottom of the sump. With the transmission fluid warm and your foot on the brake, cycle the transmission through the gears so that fluid is in all of the internal passages. Then, with the engine idling, remove the fill plug. A small stream of fluid should come out. If not, the fluid level is low.
To add fluid, you will probably need a fluid transfer hand pump, such as one manufactured by Mityvac that costs about $25, because there won’t be enough room for a funnel. With the engine still running, add fluid until some begins to pour out, and then—engine still running—tighten the fill plug to the specified torque value.
Some manufacturers, including Audi and BMW, are even more specific in their recommended procedure, insisting that the transmission fluid temperature be between 30 degrees C and 50 degrees C. (86 degrees F to 122 degrees F) when checking fluid level or adding fluid. But the Audi transmission should be cooled to ambient temperature before being refilled after draining.
But it gets even more complicated: some manufacturers require on some models, including Toyota and Volkswagen, that a proprietary scan tool be used to enable opening specific passageways in the transmission before checking fluid level.
Before attempting to check fluid level in a car without a dipstick, be sure that you know the proper, factory-specified procedure. You may be able to find that procedure on the Internet, but the best source of information remains the factory shop manual.