No one knows transmissions & torque converters like


No one knows transmissions & torque converters like 2008-sonnax-logo-white

Ts robothead 18in high trans rgb
Maybe it’s not the torque converter!

View Transmission Parts for Resolving & Preventing Torque Converter Problems

Nobody knows transmissions like Sonnax.

Sonnax transmission products are the number one choice of large transmission remanufacturers, quality valve body rebuilders, and veteran independent specialists around the world. Our innovative parts are designed to address the root cause of automatic transmission problems, allowing rebuilders to salvage valve bodies with highly effective repairs.

Which Sonnax Kit is Right for Your Rebuild?

Line Pressure Booster Kit Line Pressure Booster Kits

Affordable kit for big performance without a big price tag.

  • Affordable kit with no special tools or reaming required
  • Slightly stronger springs for a modest base line pressure increase
  • Larger boost valves for demand-based line rise without low-speed harshness
3d zip kit-box_2010-right-trans Zip Kits®

The first step in correcting common shift problems.

  • Installs quickly & easily without any special tools
  • Stops leaks so the valve body works the way it's supposed to
  • In-depth tech booklet for installation, plus diagnostics & repair
Line Pressure Booster Kit The Sure Cure®

Comprehensive kit for big problems you don't want back.

  • Restores OE shift quality
  • Repairs biggest trouble areas to reduce comebacks
  • Step-by-step instructions for comprehenseive valve/pump body restoration
Performance pack box 3-d right flat trans Performance Packs

The best parts for performance & heavy duty recalibration

  • Firmer shifts under load without low-speed harshness
  • Consistent recalibration results with tuning options
  • Improved durability
  • No special tools required

New Parts

Valve Body Separator Plate Valve Body Separator Plate

Sonnax offers direct replacement, OE-quality valve body separator plate 35740-048 for ZF8HP45 and ZF8HP70 applications. This plate incorporates a black silicon sealant bead to bond upper and low...

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Tool Kit Tool Kit

Tool Kit for 144510-01K

Oversized Pressure Regulator Valve Kit Oversized Pressure Regulator Valve Kit

GM 6T40, 6T45 and 6T50 first generation transmissions may exhibit multiple line pressure and converter-related problems due to high wear in the main pressure regulator bore. Wear at the balance ...

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Tool Kit Tool Kit

Tool Kit for 102741-07

Oversized Pressure Reducing Valve Oversized Pressure Reducing Valve

Listed Hyundai/Kia transmissions often suffer shift abnormalities caused by excess wear in the pressure reducing valve bores. This wear prevents proper regulation of oil pressure supplied to con...

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Pump Slide Spring Pump Slide Spring

Sonnax high-performance pump slide spring 104534-HD for GM 6L80 and 6L90 transmissions helps maintain consistent pump volume during line rise and at high-RPM operation.

In high-performanc...

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Tool Kit Tool Kit

Tool Kit for 144510-05K

Oversized TCC Control Valve Kit Oversized TCC Control Valve Kit

Common concerns associated with listed GM transmissions are TCC slip, TCC lining degradation, TCC slip codes, and converter apply or release issues. These problems are often caused by excess wea...

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