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

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...

Read More

Tool Kit Tool Kit

Tool Kit for 144510-03K

Oversized Pressure Regulator Valve Kit Oversized Pressure Regulator Valve Kit

Ford 6F35 transmissions may exhibit multiple line pressure and converter-related problems due to excess wear in the main pressure regulator bore. Wear at the balance spool end allows critical fl...

Read More

Isolator Valve Kit Isolator Valve Kit

Ford 6F50/6F55 and GM first generation 6T70/6T75 units may exhibit no line rise or low line pressure due to excess wear in the isolator valve bore. The isolator valve is in the main line pressur...

Read More

Bore Sizing Tool Bore Sizing Tool

When used after reaming, this tool provides exact bore sizing and superior bore surface finish, leaving bore prepared for installation of Sonnax oversized solenoid switch valve plug kit Read More

Tool Kit Tool Kit

Tool Kit for 36833-01K

Oversized Modulator Valve Kit Oversized Modulator Valve Kit

Vehicles with Ford C6 transmissions often display stacked upshifts, no kick-down, little or no line rise and/or direct clutch failure. These concerns are frequently caused by wear of the transmi...

Read More

Ring Gear Stabilizer Kit Ring Gear Stabilizer Kit

Vibrations at high speeds and broken Reverse friction plates are common problems with GM Powerglide® racing transmissions. These issues occur when the poorly supported planetary r...

Read More

View more new Transmission parts View all Transmission parts