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Home › Infiniti › 1993 › G20 Automatic › Repair and Diagnosis › Transmission › Automatic Trans › Overhaul - RL4F03A › Testing › Road Test › Road Test Procedure

Road Test Procedure

  1. Place selector lever in "P" position, and start engine. Turn engine off and repeat procedure in all positions, including "N" position. Ensure engine starts in "P" and "N" positions only. In "P" position, transaxle parking mechanism should be locked and vehicle should not move. Release parking brake to ensure parking mechanism remains locked.
  2. Start engine, move selector lever from "P" to "R" position, and note shift quality. Drive vehicle in reverse long enough to detect slippage or other abnormalities. Stop vehicle and move selector lever into "P" position.
  3. Move selector lever from "R" and "D" positions to "N" position and note shift quality. With parking brake released and selector lever in "N" position, lightly depress accelerator to ensure vehicle does not move.
  4. Move the selector lever from "N" to "D" position, and note the shift quality. Road test the vehicle while noting the upshift/downshift speeds. Upshift/downshift speeds should be close to the speeds shown in the SHIFT SPEED CHART. See Fig 1 . Also, refer to the SHIFT SPEED SPECIFICATIONS  table.
  5. Shift speeds should be checked at light, half and full throttle positions. Note when shift shock occurs during shifting. Determine if lock-up occurs while driving vehicle in appropriate gear position and at correct speed. See the LOCK-UP SPEED SPECIFICATIONS  table. Ensure transaxle does not shift to overdrive with OD switch in OFF position.
  6. When vehicle is being driven 37-43 MPH ("D" position) at half to light throttle position, fully depress accelerator pedal to ensure transaxle downshifts from 3rd to 2nd gear. When vehicle is being driven 16-22 MPH ("D2" position) at half to light throttle position, fully depress accelerator pedal to ensure transaxle downshifts from 2nd to 1st gear.
  7. Shift vehicle to "2" position and ensure vehicle starts in 1st gear. As vehicle speed is increased, ensure transaxle upshifts from 1st to 2nd gear. Further increase vehicle speed. Ensure transaxle does not upshift to 3rd gear.
  8. While driving vehicle 16-22 MPH with throttle at half to light position ("2" position), fully depress accelerator pedal to ensure transaxle downshifts from 2nd to 1st gear. Decelerate vehicle and ensure 2-1 downshift. Shift to "D" position and drive vehicle at 19-25 MPH. Shift into "2" position. Ensure 3-2 downshift occurs.
  9. Shift vehicle to "1" position. Transaxle should not upshift from 1st to 2nd as vehicle speed increases. Accelerate and decelerate vehicle to determine engine braking. Ensure engine compression acts as a brake. Drive vehicle in "2" position at 9-16 MPH. Ensure 2-1 downshift occurs when selector lever is moved to "1" position.
LOCK-UP SPEED SPECIFICATIONS (1)

Application MPH
Lock-Up ON in 4th Gear 41-66
Lock-Up OFF in 4th Gear 39-43
(1) With 1/4 throttle opening.
SHIFT SPEED SPECIFICATIONS

Application Full Throttle MPH Half Throttle MPH
1st-2nd 32-37 17-22
2nd-3rd 60-65 31-36
3rd-4th N/A 60-65
4th-3rd 93-98 39-43
3rd-2nd 55-60 25-30
2nd-1st 24-29 5-10
Fig 1: Shift Speed Chart
G93B23409Courtesy of NISSAN MOTOR CO., U.S.A.
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