8L90 Signal Accumulator Piston Kit
When rebuilding or upgrading a transmission, one of the most common wear areas is the accumulator bore. The accumulator piston is essential for maintaining proper hydraulic integrity and shift quality. Sonnax offers a drop-in signal accumulator piston kit that reconditions worn bores quickly and easily — with no reaming required.
This complete set restores performance, prevents leakage, and ensures long-term reliability. FREE UPS Ground to the contiguous United States (lower 48) if purchased with a Kit. USPS Priority Mail if purchased separately.
In stock items ship within 1-2 business days.
Picture for representation purposes only. Actual contents may vary as we continue to develop our products.
Why Upgrade to a Sonnax Accumulator Piston Kit?
- No Reaming Required: Drop-in design makes installation fast and efficient.
- Restores Hydraulic Integrity: Re-establishes VFS signal pressure circuits.
- Prevents Future Wear: Features highly wear-resistant sleeves and sealing technology.
- OE Dampening Action: Mating spring restores the factory dampening effect for smoother operation.
- Durability You Can Trust: Hardcoat anodized aluminum pistons and annular grooves combat premature wear.
Key Features of the Sonnax Accumulator Piston
- Hardcoat Anodized Pistons: Provides superior wear resistance.
- Annular Grooves: Reduce friction and extend component life.
- Wear-Resistant Sleeve: Protects bores from future wear and failure.
- Positive Sealing O-Ringed Plug: Stops leakage even in previously worn bores.
- Zip Valve™ Technology: Drop-in design ensures fast installation and dependable results.
What’s Included in Each Accumulator Piston Kit?
- (7) Sleeves
- (7) Pistons
- (7) Springs
- (7) O-Rings
- (7) End Plugs
This complete set ensures every worn bore in the circuit is restored and reinforced.
Benefits of an Accumulator Piston Upgrade
- Improved shift feel and consistency
- Reduced hydraulic leaks and pressure loss
- Longer service life for transmission components
- Fast and simple drop-in installation
- Prevents repeat repairs caused by bore wear
Frequently Asked Questions About Accumulator Pistons
What does an accumulator piston do in a transmission?
The accumulator piston regulates hydraulic pressure within the transmission, helping control clutch apply rates and improving shift quality.
Why do accumulator pistons wear out over time?
Constant hydraulic pressure and movement cause the piston bores to wear, leading to leakage, reduced pressure, and poor shift performance.
How does a Sonnax accumulator piston kit prevent future wear?
The kit uses a hardcoat anodized aluminum piston, annular grooves to reduce friction, and wear-resistant sleeves that reinforce the bore against future damage.
Do I need special tools to install this accumulator piston kit?
No. The Sonnax design is a drop-in solution that requires no reaming or machining, making installation straightforward for both professionals and DIYers.
Can replacing the accumulator piston improve shift quality?
Yes. By restoring proper hydraulic sealing and pressure regulation, the Sonnax accumulator piston kit improves shift feel, reduces flare, and extends transmission life.
