Vehicle Moves In D and S, But Not In R (Or Moves Forward In R)

Vehicle moves in D and S, but not in R (or moves forward in R)

Diagnostic Procedure:

1. Shift fork shaft stuck

2. 5th accumulator defective

3. 5th clutch defective

4. Reverse gears worn or damaged

5. Reverse idler gear shaft/holder worn or damaged

6. Reverse selector or reverse selector hub worn or damaged

Also check for:

- Check for a missing shift fork bolt on the shift fork shaft.
- Check the shift fork shaft detent for wear and damage.
- Check for a stuck servo valve in the regulator valve body, and check the O-ring for wear and damage.
- Check the stall speed in R. A/T Stall Speed Test
- Check the 5th clutch pressure. A/T Pressure Test
- Inspect the 5th clutch for wear and damage.
- Inspect the clutch piston, the clutch piston check valve, and the O-rings. Check the spring retainer for wear and damage. Inspect the clearance between the clutch end-plate and the top disc. If the clearance is out of tolerance, inspect the clutch discs and the plates for wear and damage, and inspect the clutch wave-plate height. If the discs and the plates are worn or damaged, replace them as a set. If the clutch wave-plate height is out of the tolerance, replace the clutch wave-plate. If they are OK, adjust the clearance with the clutch end-plate.
- Check the 5th accumulator piston, the O-ring, and the spring in the accumulator body for wear and damage.
- Inspect the reverse idler gear shaft/holder for wear and damage.
- Inspect the reverse selector gear teeth chamfers, and inspect the engagement teeth chamfers of the countershaft 5th gear and the reverse gear. Replace the reverse gears and the reverse selector if they are worn or damaged. If the transmission makes clicking, grinding, or whirring noises, also replace the mainshaft 5th gear, the reverse idler gear, and the countershaft 5th gear.