Pin bore wear at the 1st/2nd accumulator circuit causes leaks and burns up clutches and bands. The Sonnax oversized accumulator pin kit 54250-04K includes a reamer to oversize the piston pin bore. The oversized pin allows for tighter clearance between the pin and piston and restores the integrity of the circuit. A replacement accumulator pin kit 54250-05K is also available without the reamer, as the reamer from 54250-04K can be reused.
This kit contains enough parts to repair 10 accumulator pistons. The early model TH180 has a removable E-Clip retainer holding the accumulator piston and spring in place. The late model TH180 has a non-removable fixed head holding the accumulator piston and spring in place. The Sonnax pin will work with either of these applications.