Rules For Cleanliness When Working On The Transmission

Thoroughly clean all unions and the adjacent areas before disconnecting.
Place removed parts on a clean surface and cover. Use sheeting and paper. Use lint-free cloths.
Carefully cover or seal open components if repairs cannot be carried out immediately.
Only install clean components: do not remove replacement parts from their wrapping until they are ready to be installed.
Always replace O-rings, sealing rings and gaskets.
Lightly lubricate O-rings with ATF or Vaseline before inserting to prevent them being trapped and damaged when assembling.
Use only ATF in the parts of the transmission where ATF is the specified lubricant. Other types of lubricant can cause problems with the hydraulic actuation of the transmission.
Check the following fluid levels after installation and top off as necessary: ATF in the planetary gearbox. See SERVICING - 09G article.