Mitsubishi bushing failures As all readers have experienced, Mitsubishi torque converter failures are quite common due to low pump pressure. This is typical of most Mitsubishi converters causing the front pump bushing to bond to the impeller hub.
The reason is quite simple. The Mitsubishi converter does not allow the valve body to charge the torque converter with oil when the transmission in located in park.
After rebuild, the transmission is filled with fluid in park taking several minutes to do so with no lubricant, thus causing the front pump bushing to burn up.
Many rebuilders modified the manual shift valve by grinding it flat on one of the partitions of the manual shift valve. This practice is somewhat successful, but it is recommended to replace the shift valve with a new, updated Sonnax part. Call your Sonnax part representative for more information and availability. It is highly recommended on every rebuild.
Also, the factory ground strap is sometimes omitted after reinstallation. This also can aggravate the same problem, causing small arcs between the bushing and the torque converter hub. In reality, the torque converter is being grounded improperly causing this problem. It is suggested to replace any worn ground straps with a heavy duty, universal cable. This will ensure customer satisfaction.
Found in issue 04, 2004