Excessive shock or flares on 3-4 upshift or 4-3 downshift
Check for a stored DTC, and check for loose connections.
Test the solenoid valve function with the HDS.
Inspect the A/T clutch pressure control solenoid valve body gasket, ATF feed pipes, and O-rings for wear and damage.
Check for clogged orifice in the separator plate. If the orifice is clogged, remove it and clean the separator plate orifice.
Check the 3rd and 4th clutch pressures.
Inspect the 3rd and 4th accumulator pistons, O-rings, and springs for wear and damage in the servo body.
Inspect the mainshaft, secondary shaft, 3rd clutch, and 4th clutch for wear and damage.
Inspect the clutch piston, clutch piston check valve, and 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 plates for wear and damage, and inspect the clutch wave-plate height. If the discs and plates are worn or damaged, replace them as a set. If the wave-plate height is out of tolerance, replace the wave-plate. If they are OK, adjust the clearance with the clutch end-plate.
Inspect the 3rd and 4th clutch feed pipes.
If the 3rd clutch feed pipe is scored, replace it and the O-rings under the feed pipe flange.
If the 4th clutch feed pipe is scored, replace it and the O-rings under the feed pipe flange.
Replace the secondary shaft if the bushing for the 4th clutch feed pipe is loose or damaged.
Replace the mainshaft if the bushing for the 3rd clutch feed pipe is loose or damaged.
A/T clutch pressure control solenoid valve B defective
A/T clutch pressure control solenoid valve C defective
Foreign material in separator plate orifice
3rd accumulator defective
4th accumulator defective
3rd clutch defective
4th clutch defective