No Fourth Gear, or Slips in Fourth Gear

Check	Causes
DEFINITION: A large engine RPM is noted in fourth gear or no vehicle forward speed increase. Shifts into fourth gear are soft or do not occur.
Control Valve Body Accumulator Assembly	3-4 shift valve stuck applied 3-4 shift control valve stuck applied
Direct and Reverse Clutch	Damaged or worn piston (406) Damaged or worn clutch plates Damaged ball check valve (405)