Shift Point Road Tests

SHIFT POINT ROAD TEST

NOTE: This check will determine if the electronics, governor, and shift control valves are functioning properly. Check light throttle upshifts with selector in overdrive range (approximately 10 in Hg vacuum).

1. The transmission should start in 1st gear, shift to 2nd, shift to 3rd, shift to 4th, and then lock the converter clutch.

Shift Speed Chart:

NOTE: Converter lockup is sometimes difficult to feel, therefore a vacuum gauge and tachometer should be used to determine lockup shift points. Refer to the Shift Speed Chart for actual shift points and vehicle speed.

2. When selector lever is in D position, the transmission will make all automatic up-shifts except the 3-4 shift.
3. When selector lever is in 2 position (2nd gear), the transmission can operate only 2nd gear.
4. With transmission in 3rd gear and road speed over 45 mph, the transmission should shift to 2nd gear when the selector lever is moved from D or 2 (2nd) to 1 (1st). This check determines if the governor pressure and shift control valves are functioning properly.
5. If vehicle is traveling at approximately 45 mph and the selector lever is moved from Overdrive to 1, or D to 1 (closed throttle), the transmission will immediately downshift to 2nd gear. As road speed drops below 30 mph the transmission will downshift to 1st gear.
6. For a coastdown from approximately 45 mph with the transmission in Overdrive and at closed throttle, the downshift sequence is as follows:
a. converter clutch unlocks electronically when accelerator pedal is released.
b. As vehicle speed drops, 4-3, 3-2, and finally 2-1 downshifts occur.