The 4T65E (&HD) transmissions frequently suffer from a soft 1-2 upshift problem and delayed engagement of the reverse gear. Both of these symptoms are a result of the boost valves wearing away the wall of the soft boost sleeve. This allows pressure to be bled off.

If you're rebuilding your transmission you'll want to upgrade to our reinforced boost valve & sleeve kit. Our kit features:

• Hard, anodized valves for better fit (perfect center) and less wear
  
• Aircraft quality boost sleeve w/ holes to distribute oil evenly
• No machining required. Easy install (assuming an open valve body)

• 1997 - Current applications using the 4T65E transaxle
• 1997 - Current applications using the 4T65E-HD transaxle