Signal Accumulator Piston Kit Sonnax 8L45 8L90

Sonnax Signal Accumulator Piston Kit – Fits GM 8L45 & 8L90

In GM 8L45 and 8L90 transmissions, excessive wear in the signal accumulator piston bores of the solenoid body casting can lead to shift issues, low line pressure, torque converter apply problems, and burnt clutches. These problems occur when VFS signal pressure leaks through worn bores, disrupting proper control of pressure circuits and clutch apply timing.

The Sonnax signal accumulator piston kit 154740-06K is a direct replacement solution that restores control pressure without the need for reaming. This drop-in kit seals worn bores, revives VFS pressure accuracy, and improves transmission performance with long-lasting, wear-resistant components.

Features:

• Precision-machined pistons with hardcoat anodizing for increased durability
• Annular grooves reduce friction and slow future wear
• Wear-resistant sleeves restore bore integrity
• O-ringed end plugs provide effective sealing in damaged or worn bores
• Matching springs included to replicate factory dampening behavior
• All components are drop-in ready—no special tools or machining required

Kit Includes:

• 4 Sleeves
• 4 Pistons
• 4 Springs
• 4 End Plugs
• 6 O-Rings (2 extra)

Common Symptoms:

• Erratic or soft shifting
• Insufficient line pressure
• Converter clutch not applying
• Hydraulic-related DTCs
• Burnt or slipping clutches

Cause: Excessive wear in signal accumulator bores causes loss of VFS pressure, which compromises the regulation of line pressure, shift quality, and converter clutch control.

Correction: Install the Sonnax signal accumulator piston kit to restore VFS pressure circuit sealing, improve shift consistency, and extend transmission life.

Transmissions: 8L90 2014-UP, 8L45 2016-UP

Vehicle

CADILLAC
ESCALADE, ESCALADE ESV, ATS, CT6, CTS 2015-2016 8 SP RWD V6 3.6L
CHEVROLET
CORVETTE, SILVERADO 2014-2016 8 SP RWD V8 6.2L
CAMARO 2015-2016 8 SP RWD L4 2.0L V6 3.6L V8 6.2L
CANYON, COLORADO, SILVERADO 2016 8 SP R/4WD L4 2.5L
GMC
YUKON XL 2014-2016 8 SP R/4WD V8 5.3L 6.2L
SIERRA 2014-2016 8 SP R/4WD V8 5.3L 6.2L

Alternate Words: transmission and specialty driveline components