Symptoms:

  • Delayed Forward
  • Forward slip
  • C1 Clutch burned
  • Harsh Forward
  • Flare shifts

Cause:

Wear at the accumulator piston bore in the valve body or on the critical accumulator piston diameters allows apply oil to exhaust.

Correction:

Sonnax drop-in accumulator piston kit incorporates an O-ring for positive sealing plus annular grooves for better centering and wear prevention.

U660E, U660F, U760E, U760F

C1 Accumulator Piston Kit
Part No. 47740-12K

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

Wear at the accumulator bores or on the accumulator piston critical diameters in Toyota/Lexus listed units is very common. The C1 accumulator piston is used during apply of the C1 (Forward) clutch. Wear allows clutch apply oil to exhaust, resulting in harsh or delayed Forward engagements, burned C1 clutch, or slipping and flares in Forward gears. Sonnax C1 accumulator piston kit 47740-12K incorporates an O-ring for positive sealing, even in worn bores.

  • O-Ring provides positive seal, even in worn bores
  • Annular grooves provide better piston centering and wear prevention
  • Hardcoat anodized aluminum piston combats premature wear
  • Drop-in Zip Valve parts install quickly and easily
  • Piston
  • O-Rings (2) 1 Extra

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, U760E, U760F C1 Accumulator Piston Kit 47740-12K
  • U660E, U660F, U760E, U760F C1 Accumulator Piston Kit 47740-12K

You need this if...

A vacuum test at the port indicated fails to hold at least 18 in-Hg (Figure 1), or visual wear in bore or on the piston is detected (Figure 2).

U660E, U660F, U760E, U760F C1 Accumulator Piston Kit Vacuum Test Locations