Symptoms:

  • Delayed Reverse
  • Low line rise in Reverse
  • B2 Clutches burned

Cause:

Wear of the reverse boost valve sleeve allows line pressure to escape to exhaust.

Correction:

Sonnax drop-in reverse boost valve kit features upgraded materials and tighter clearances to prevent wear and restore proper hydraulic control.

U660E, U660F

Reverse Boost Valve Kit
Part No. 47740-17K

You need this if... View Instructions Find a Distributor

Vehicles with Toyota/Lexus U660E, U660F transmissions may exhibit insufficient line rise in Reverse, delayed Reverse engagement and/or a burned B2 brake. These problems may be caused by continuous oscillation of the steel boost valve within the cast aluminum boost sleeve, creating excessive wear and a path for line pressure to either leak to exhaust or leak to the EPC boost circuit and create high line pressure conditions.

Sonnax Reverse boost valve kit 47740-17K has upgraded materials and minimal clearances to prevent wear and restore proper hydraulic control.

  • Sleeve is manufactured from highly wear-resistant billet aluminum to prevent excess wear
  • Restores proper line rise
  • Hardcoat anodized aluminum valve combats premature wear
  • Drop-in Zip Valve parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs
  • Valve
  • Sleeve

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

Toyota/Lexus U660E/F, U760E/F Valve Body Layout

Toyota/Lexus U660E/F, U760E/F Valve Body Layout
  • U660E, U660F Reverse Boost Valve Kit 47740-17K
  • U660E, U660F Reverse Boost Valve Kit 47740-17K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

U660E, U660F Reverse Boost Valve Kit Vacuum Test Locations
U660E, U660F Reverse Boost Valve Kit Vacuum Test Locations