Automatic transmission manufacturers all tend to adopt industry-wide standards. One standard that has endured for many years is the use of oil pan charts, which are produced by transmission parts companies and widely distributed to parts stores and transmission repair shops. These charts list every transmission oil pan shape imaginable in great detail, right down to the number of bolts used to hold the pan in place. The 700 R-4 is no different. In fact, it is one of the easier transmissions to identify. Being an overdrive model, your first identifying clue is the shift indicator in the car. If it has an O for overdrive, and the year model is between 1982 and 1990, chances are you have a 700 R-4 transmission.
Jack up the car and install jack stands under the frame. Lower the car and make sure it is secure before going underneath to examine the transmission.
Inspect the transmission pan. If it is a rectangle, narrow at the front and rear, longer on the sides, it is probably a 700 R-4 transmission. Verify this by counting the number of bolts holding the pan in place. At a glance, there are three bolts in the front and three in the rear. There is also an equal number on each side, and if your count equals five per side for a combined total of 16 bolts, it is a 700 R-4 transmission.
Confirm your findings by year model and production date. In 1991 the 700 R-4 was extensively modified and renamed the 4L-60E. Be certain of the exact production date and verify the transmission model. Although similar in appearance, there are slight differences. And in reality, the two designs are worlds apart. The 4L-60E, E standing for electronic, has a much larger wiring harness and is controlled in a completely different manner. The two will not interchange.
Jack up the rear of the car and remove the jack stands. Lower the car to the ground.
