In 1999, Dodge had two vehicles bearing the “1500” nomenclature: the Ram and Ram Van. The 1999 Dodge Ram 1500 was the smallest of the automaker’s full-size pickup trucks; the Ram Van 1500 was the automaker’s smallest full-size van. The two vehicles differed greatly in appearance, but they had the same engine and transmission setups. The transmission speed sensor — technically called the “vehicle speed sensor” — sends a signal to the vehicle’s computer, letting it know how fast the vehicle is going. The computer then makes adjustments to other systems as needed. When this sensor fails, the vehicle's speedometer may become inoperative or inaccurate, and the driver may experience difficult transmission shifting.
Raise the front of the 1500 with a floor jack, and set jack stands under the vehicle’s frame rails. Lower the vehicle onto the jack stands.
Crawl beneath the Dodge until you reach the transmission output-shaft housing — the tapered housing on the rear of the transmission. Look to the driver’s side of the output-shaft housing and find the electrical component connected to it — this is the vehicle speed sensor.
Position a drain pan under the vehicle speed sensor to catch any fluid that may leak.
Pull the locking tab on the sensor’s wiring harness, and unplug the harness from the sensor.
Remove the bolt securing the output-shaft sensor to its adaptor — do not remove the bolt securing the adaptor to the transmission — and pull the vehicle speed sensor from the adaptor.
Apply a thin coat of new ATF Plus 3 transmission fluid to the O-ring on the vehicle speed sensor.
Insert the vehicle speed sensor into the adaptor. Hand-tighten the sensor’s screw. Tighten the screw to 20 foot-pounds with a torque wrench and socket.
Reconnect the wiring harness to the receptacle on the vehicle speed sensor.
Raise the 1500 off the jack stands with a floor jack and remove the jack stands. Lower the vehicle to the ground.
Start the vehicle and allow it to idle until it is warm (the temperature gauge reads about halfway).
Hold the brake pedal and shift the gear shifter through each gear. Place the gear shifter back into its “Park” position.
Remove the transmission level dipstick from the engine compartment and wipe the oil off it with a clean, lint-free cloth. Reinsert the dipstick and pull it out again. Check that the level is within the “Full” range on the dipstick.
Insert a long-neck funnel into the dipstick tube and add ATF Plus 3 transmission fluid as needed.
Take the old transmission fluid to a used-automotive-fluid recycling center. Some auto parts stores take this fluid free of charge.
