Checking automatic transmission fluid is quite simple and straight forward, right? Well not really. Like so many things today, something that should be simple has become quite complex. The following is meant to serve as a guide to help simplify the process.
While procedures vary from vehicle to vehicle, certain things remain constant.
The vehicle should be at normal operating temperature. Ten minutes of driving should accomplish this.
The vehicle needs to be level.
Before beginning, start the vehicle and move the shifter slowly through all gears.
Most vehicles are checked in Park, with the engine running and parking brake set.
On vehicles with a dipstick, both sides of the stick should be read and the lowest reading is the correct one.
If there is fluid on the stick, then a void, then more fluid, the lowest reading is the correct one.
Check the reading at least twice, wiping the dipstick clean between readings.
Both sides of the stick read full, this is an accurate reading, assuming above conditions are met.
One side of the stick reads full, this is from splash. The lowest reading is the actual fluid level, assuming above conditions are observed.
Another false indication, the lowest solid reading on the stick is the correct level. The reading above the air gap is from splash and is not accurate.
Many automatic transmissions today no longer have a dipstick.
The trend appears to be away from dipsticks and toward special procedures and fluids in automatic transmissions. The Ford Explorer 5R55(W, S and N) are common examples. Some require special tools and methods we cannot go into here. The following illustrations are for Ford and may be typical of others.
In the bottom of the pan are two hex shaped nuts. The larger is the drain plug. The small, in the center of the larger, is the check and fill plug. When the small plug is removed, with the vehicle level and fully warmed, fluid will drip from the opening.
If the fluid is low, the small internally raised tube, will prevent if from coming out. The proper amount is slowly drip and too much fluid will run out. A special tool is used to fill such a unit. Also be extremely careful when removing any external bolts. Some secure components within the transmission. Though they may look like a fill plug, removing them can create problems that can only be corrected by disassembling the transmission.
As important as checking procedure is installing the proper type of fluid. There are dozens of transmission fluids on the market today. Using the improper fluid can cause shifting concerns, void a transmission's warranty and possibly damage the transmission.
You can also trust AGCO Automotive to check and service your transmission properly. The right procedures, the right parts, professionally done, that's the AGCO way.
