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Sonnax Transmission Parts

Sonnax Transmission Parts

Since 1978, Sonnax Transmission Company has specialized in the cutting-edge design of top-quality performance and OEM replacement transmission parts. Summit Racing carries...

Since 1978, Sonnax Transmission Company has specialized in the cutting-edge design of top-quality performance and OEM replacement transmission parts. Summit Racing carries a large selection of Sonnax transmission and drivetrain parts, including slip yokes, throttle cable brackets, input drum reinforcement kits, hydraulic line pressure booster kits, and more. Order your Sonnax transmission parts from Summit Racing today!

Since 1978, Sonnax Transmission Company has specialized in the cutting-edge design of top-quality performance and OEM replacement transmission parts. Summit Racing carries a large selection of Sonnax transmission and drivetrain parts, including slip yokes, throttle cable brackets, input drum reinforcement kits, hydraulic line pressure booster kits, and more. Order your Sonnax transmission parts from Summit Racing today!

Part Groups

Results 1 - 24 of 192

Sonnax Slip Yokes

Sonnax slip yokes are forged, not cast, for greater strength, and they undergo a precision-machining process to guarantee exceptional balance and minimal runout. They are 100 percent leak-tested, the seal plug is O.D. ground for superior seal, and yokes are air-tested to 40 psi. Sonnax slip yokes are available in different lengths and tooth counts to fit your specific transmission application.

4.85 out of 5 stars ( 107 )

$156.02

$305.44

Sonnax Zip Kits

Sonnax Zip kits are engineered to cure common problems associated with today's automatic transmissions. Sonnax Zip kits eliminate: * Burnt clutches * Line pressure instability * Loss of fuel economy * No line rise * Pressure loss * Shift concerns * TCC apply and release concerns * TCC codes * Pressure switch codes

4.78 out of 5 stars ( 9 )

$99.59

$235.14

Sonnax Flanged Yokes

Sonnax flanged yokes will complete your driveshaft connection. These high performance 6061-T6 aluminum parts are precision-machined to be stronger than the original cast steel yokes, as well as being lighter in weight. Sonnax builds these yokes for exceptional balance and superior craftsmanship, for a show-quality driveline.

5.0 out of 5 stars ( 22 )

$45.50

$282.02

Sonnax Clutch Hubs

Many Sonnax clutch hubs are designed for the extra-duty requirements of drag racing with Powerglide and other GM transmissions, for instance. Machined from a high-quality medium carbon steel forging, most hubs will accept five friction discs for the added load capacity needed in high horsepower race cars. All splines and thrust surfaces are precision-machined to exacting tolerances, and the unique lube hole pattern is designed to reduce drag on the friction discs in low gear. Sonnax clutch hubs are also available with or without lightening holes to reduce rotational weight.

4.63 out of 5 stars ( 16 )

$32.24

$135.23

Sonnax Input Carrier Kits

Sonnax input carrier kits transform OE wide-ratio automatic transmissions into a close ratio for game-changing acceleration on the track. Manufactured and engineered for outstanding durability, these kits keep your engine in the optimal power band, while allowing a longer pull in first and second gears, improving consistency and performance. The input carrier gears are precision-ground to OE standards and feature thrust washers with a highly wear-resistant, PTFE-coated material, plus a thicker captured bearing. Lube channels direct oil to the pinion pins, and the carrier can be disassembled for inspection and service. Stay in the power band with Sonnax input carrier kits.

5.0 out of 5 stars ( 3 )

$855.99

Sonnax Vacuum Test Stand Kits

Vacuum testing is an efficient way to evaluate valve and valve body wear. A worn valve or valve body bore can result in incorrect pressures in the transmission, which may lead to poor performance or failure of the transmission. In order to determine if a valve/bore is worn, or to make sure a valve repair has been performed correctly, the proper vacuum testing equipment is required. Sonnax vacuum test stand kits help fill this need. Whether you're diagnosing a problem valve body or verifying your remanufacturing process, the Sonnax vacuum test stand kit will be an invaluable tool. Product details: * Quick, easy testing of valve bores * Yields repeatable numerical results for comparison and documentation * Anodized finish will stand up to years of use * Test stand features high-quality brass needle valves and a built-in test orifice for simple calibration * Clear Sonnax test plate and silicone pad ensure easy, securely-sealed testing Kit contents: * Vacuum test stand * Test plate * Vacuum plate sealing pad * Vacuum test foam pad * Push-to-connect fitting * Assorted testing tips (6) * Flexible tubing * Flared tubing with flared nut * Testing tip adapter tube

4.88 out of 5 stars ( 8 )

$274.99

Sonnax Valve Bodies

Sonnax universal remanufactured valve bodies have been uniquely designed to fit a variety of '99-later Chrysler applications, regardless of OE checkball or solenoid configuration. The convenience of stocking one SKU number for various applications saves time, money and interchangeability confusion. The channel casting has been resurfaced to SAE recommended flatness and surface finish. The seasoned casting warpage is now eliminated, removing cross-leaks and manufacturing burrs that resulted in clutch distress and shift complaints. A new separator plate is also installed, along with gaskets, to seal the critical surfaces between the valve body and channel casting. Heavy-duty/high performance accumulator pistons with dual-guide seals are installed to prevent piston-to-bore scuffing and restore clutch pressures due to leakage. Patented Sonnax valves are installed to restore hydraulic pressures and eliminate shift complaints, trouble codes, converter concerns and overdrive clutch distress. Their patented accumulator cover plate—made from stronger, thicker material and secured with additional screws—is also installed to prevent flexing or breakage. To guarantee the highest level of operational performance, these remanufactured valve bodies are tested on state-of-the art equipment to verify that pressures match OE specification. Product notes: * One SKU fits all applications, saving time, money and confusion * Resurfaced OE channel casting eliminates warpage, burrs, and cross-leaks cost effectively * New separator plate and gaskets provide critical seal between cast surfaces * Patented Sonnax valves and pistons restore hydraulic integrity of circuits to eliminate shift complaints and clutch distress * Patented Sonnax accumulator cover plate stronger than OE to prevent flexing and breaking

5.0 out of 5 stars ( 1 )

$318.24

$680.85

Sonnax Premium Planetary Assemblies

Sonnax premium planetary assemblies are available in various configurations to meet different build requirements. The output shaft is available in the OEM length or short length, and the billet-machined drum flange in 12-tooth or 24-tooth. They are a big step up from standard case-hardened and tempered gears. Sonnax's top-quality racing gear material (SAE9310), combined with a freeze-tempering process (-150 degrees F), results in gears with improved grain structure and stability--tougher and more resistant to wear. Sonnax premium planetary sets are fully assembled and ready to install.

Not Yet Reviewed

$669.08

$1,205.99

Sonnax Externally Adjustable Low/Reverse Servo Kits

Sonnax externally adjustable low/reverse servo kits make band maintenance quick and easy. They offer an ideal way to improve reliability and make staging more consistent and predictable. Checking L/R band adjustment after repeated use is good practice. Unfortunately, OE servos with steel covers are difficult to adjust in a vehicle, so a quick check with such a servo installed is impractical for most racers. Sonnax externally adjustable servos provides an improved design that makes checks and adjustment of the L/R servo easy. There is no cover or access plug to remove because the adjuster itself extends through the cover. A quick check is done simply by pushing on the end of the adjuster and observing the movement of the piston relative to the servo cover. Select the kit designed for your transmission. Features: * Quickly check and adjust the low/reverse band to prevent trans-brake malfunction * Unique servo cover and adjuster design makes in-vehicle band service easy * Works with or without OE 1-2 accumulator piston Included: * 6061 Anodized billet aluminum cover * Piston * Pin * Jam nut * Cover seals -- Two PTFE, one extra * Piston seal * Cover O-ring * Pin O-ring Kit for TH400 will also include: * Cover flange O-ring * Bolts (6) * Washers (6)

Not Yet Reviewed

$353.26

Sonnax SmartShell Heavy-Duty Reaction Shell Kits

Sonnax SmartShell heavy-duty reaction shell kits prevent damage to the rear planetary assembly, as well as providing a reinforced shell. Stripped or cracked shells in GM 4L60, 4L60-E, 4L65-E and 4L70-E units are a common problem, but strengthening the shell alone does nothing to address the equally common problem of preventing thrust loads from overwhelming rear captured planetery bearings. From daily jobs to extreme builds, the Sonnax SmartShell heavy-duty reaction shell kits are the only way to prevent shell failure and protect the bearing.

4.71 out of 5 stars ( 21 )

$124.62

Sonnax Primary and Secondary Pressure Sensors

No one knows transmissions like Sonnax, which is why their primary and secondary pressure sensors work exactly like your OEM parts. Gearbox pressure sensors determine the hydraulic oil pressure in various applications and help to specify the shifting pressure more accurately. This type of sensor may fail to function under hostile conditions or simply wear over time. When that happens, help keep your drivetrain running optimally with the Sonnax primary and secondary pressure sensors designed for your application.

5.0 out of 5 stars ( 1 )

$93.90

Sonnax Smart-Tech Direct Clutch Drum and Shaft Kits

Failure of the intermediate stub shaft and direct drum are almost inevitable when transmissions are pushed to the limit. To maximize durability and improve clutch capacity in heavy-duty/performance vehicles, Sonnax offers Smart-Tech direct clutch drum and shaft kits, the first upgrade to eliminate every critical weakness. Most failures in these units occur where the direct drum and stub shaft connect. Even other aftermarket upgrades that rely on a heavy-duty shaft will sheer in this area under extreme conditions. Unlike two-piece assemblies, the all-in-one Smart-Tech easily handles the highest horsepower/torque levels. The unique one-piece clutch drum with integrated stub shaft is precision machined from high-strength steel to guarantee there are no splines to strip from the drum or weaken the shaft. The shaft itself is significantly thicker and 2 times stronger than the original. Due to its larger diameter, the integrated shaft must be used with the kit's custom, heavy-duty sun gear. Insufficient holding power is another area where many transmissions fall short, but installing thinner aftermarket steels and backing plates to increase clutch capacity isn't ideal. Those components increase clutch pack flex and heat build-up, making them the primary cause of repeat burn-up. To improve both performance and long-term reliability, the Smart-Tech's custom drum and piston hold an OE backing plate and seven OE frictions for 17 percent more clutch capacity than the six-friction stack-up. Sonnax Smart-Tech direct clutch drum and shaft kits feature: * One-piece design that eliminates weak point where drum splines strip and shafts break * Rugged shaft is 50 percent thicker and twice as strong as OE * Custom drum and piston deliver 17 percent more clutch capacity with optimum protection against burn-up * High-strength drum and shaft are precision-machined from hardened 8620 steel * Unique sun gear is precision-machined from 9310, heat-treated steel

5.0 out of 5 stars ( 1 )

$754.00

$1,537.27

Sonnax Shift Improver Performance Packs

Sonnax shift improver performance packs combine innovative heavy-duty performance calibration for firmer shifts under load without sacrificing low-speed drivability. The precision components in these kits upgrade your transmission for maximum achievement and durability by recalibrating pressures, recalibrating shift accumulation, and including improved parts for areas that commonly wear. They are suitable for any heavy-duty application and are a critical foundation for other upgrades when modifying the transmission for high performance use. Sonnax shift improver performance packs additional facts and features: * Shorter shifts, which get progressively firmer with load * Faster pressure increase and higher overall pressure for greater clutch/band holding power * Three ultra-reliable, patented, billet pinless accumulator pistons * Unique 1-2 accumulator spring combination for shifts with character * Improved high rpm pressure * Third accumulator valve gets the 2-3 right the first time, every time * Consistent results, no guessing on calibration * Prevents worn accumulators and separator plate * Optional TCC on-off conversion prevents excess TCC pressure

5.0 out of 5 stars ( 6 )

$166.99

$356.54

Sonnax Heavy-Duty Remanufactured Valve Bodies

Sonnax heavy-duty remanufactured valve bodies are built to overcome chronic shift and converter clutch apply complaints. It provides firmer shifts and a moderately increased pressure curve to improve performance, especially in truck and towing applications. Numerous Sonnax valve upgrades are included to restore hydraulic clearances that lead to shift complaints, clutch distress, converter complaints and codes, solenoid issues and pressure problems. Line pressure rise has been moderately increased to overcome shift complaints, delayed engagements, and to increase holding power to the clutches. To guarantee the highest level of operational performance, this remanufactured valve body is tested on state-of-the art equipment to verify that solenoid feed, clutch, converter, and line pressures match or exceed OE specifications. Choose your preferred kit packaged for your transmission. The valve body includes the following: * Oversized TCC regulator valve and sleeve, and limit valve spring for firmer TCC application * O-ringed bore plugs and abuse plugs * New accumulator control valve and sleeve with spring * Oversized AFL line up * New forward accumulator piston and seal * New pressure switch manifold * New EPC solenoid * New TCC PWM solenoid Kit contents: * Remanufactured valve body * Separator plate * Upper case gasket plate * Lower valve body gasket plate * 1-2, 3-4 accumulator springs * EPC solenoid harness adapter for 2003 to later units * Sonnax line pressure booster kit

4.67 out of 5 stars ( 3 )

$372.32

$582.46

Sonnax Heavy-Duty One-Piece Input Shafts

No weak link! Sonnax heavy-duty one-piece input shafts are custom-forged from one solid piece of ultra-high-strength 300M steel. Much better than the weak OE 2-piece shaft/hub design, this single piece delivers a more robust build that will work hard longer. With durability and performance features which are second to none; your only choice should be Sonnax heavy-duty one-piece input shafts.

Not Yet Reviewed

$440.14

$678.70

Sonnax Automatic Transmission Case Bushings

Sonnax automatic transmission case bushings are made to locate the carrier output shaft assembly. These bushings are a direct OE replacement. Sonnax automatic transmission case bushings are made from high-quality materials and is a required part in any high-quality rebuild.

5.0 out of 5 stars ( 14 )

$4.44

$58.94

Sonnax Super-Hold Servo Kits

Sonnax Super-Hold servo kits offer increased apply area over the OEM servo for more holding force between shifts. They are manufactured from anodized aluminum and include mounting seals and hardware for your specific transmission model. Their improved seal design will conserve pump volume.

4.84 out of 5 stars ( 25 )

$91.85

$292.41

Sonnax Automatic Transmission Governors

A bad governor will result in a sudden loss of upshift. Sonnax automatic transmission governors will restore proper function on select automatic transmissions. Their governor gears are excellent replacement components and they are made of premium materials to provide a precise fit with OE quality and function for long-lasting performance.

4.4 out of 5 stars ( 20 )

$145.67

$170.21

Sonnax Smart-Tech Drum Modules

Sonnax Smart-Tech drum modules for racing GM TH400 transmissions improve on-track performance and consistency, leading to quicker ETs, more wins, and greater reliability. The TH400 is preferred for its overall durability and multitude of available ratios, but is known to be heavier and less efficient than the popular two-speed Powerglide. Part of the TH400 inefficiency results from the fact that the direct drum counter-rotates, spinning backwards in 1st gear, brakes to a complete stop on the 1-2 shift, then goes from 0 RPM to input RPM on the 2-3 shift. Significant energy is wasted through this cycle that robs power, upsets traction on the shifts, and contributes to broken internal parts. Compared to aluminum direct drums, the Smart-Tech drum module reduces the weight of the counter-rotating components by over 3.3 lbs.! And more significantly, because the weight of the Sonnax counter-rotating parts is closer to the centerline, there's a 68 percent reduction in energy required to stop and restart during the 1-2 and 2-3 shifts. The benefits are increased wheel horsepower, better acceleration, less shock on the shifts, and improved durability. * Complete kit (34555-01K) replaces both forward and direct drums and includes everything from intermediate sprag to the pump; a selection of Sonnax input shafts is available separately. * 100 percent new content, no used core pieces * Includes larger-diameter, 36-element sprag and sprag race that works with OE intermediate clutches * Includes six-friction forward clutch pack and seven-friction direct clutch pack Contents: * Forward Piston Housing * Forward Piston * Forward Piston Return Springs (16) * Forward Spring Retainer * Forward Snap Ring * O-Ring 1.674 in. * Lip Seals (2) * Direct Housing Assembly * Direct Piston * Direct Piston Return Springs (26) * Direct Spring Retainer * Direct Snap Ring * O-Ring 2.737 in. * Sprag Shaft * Front Sprag Retainer Plate * Heavy-Duty Sprag 36 Element * Outer Sprag Race * Rear Sprag Retainer Plate * Sprag Retainer Screws (4) 6-32 x 5/16 in. * Quad Ring Seals (2) * Anti-rotation Seal Rings (2) * Drum * Pressure Plate * Outer Snap Rings (4) * Bearing Small * Forward Clutch Hub * Bearing Large * Direct Clutch Hub * Steel Clutch Plates (4) .060 in. * Steel Clutch Plates (11) .077 in. * Friction Clutch Plates (13) .080 in. * Clutch Separators (60) .103 in.

Not Yet Reviewed

$3,052.40

Sonnax Extreme Duty Main Shafts

Main shaft failure is a common problem in extreme duty GM TH400, 4L80-E and 4L85-E units. OE and aftermarket shafts simply don't hold up in extreme horsepower applications, leading to spline twist and shaft breakage. Sonnax replacement extreme duty main shafts are manufactured from an exceptionally tough high-strength Aermet steel alloy with proprietary heat treatment for unrivaled performance and durability. An advanced torsional design with spline and cross-hole refinements make these the most durable 1 in. main shafts available. These shafts withstood extensive track and lab testing with unbroken results in the most extreme applications. Additional details: * Recommended for applications above 1,000 hp * Top-notch engineering and precision manufacturing deliver unrivaled performance and durability in the 1 in. stock size * Rear spline prevents the rear internal gear journal-end from twisting off by engaging the full internal spline of the gear * Extensive in-vehicle and lab testing with unbroken performance

Not Yet Reviewed

$978.48

Sonnax Heavy-Duty Reaction Shaft Kits

Sonnax heavy-duty reaction shaft kits are universal to fit all years and all input carriers. Reaction shafts used in high-torque applications, and especially in heavy vehicles, suffer from two common issues that require replacement. The splines that engage the rear planet can twist and the splines that engage the ring gear wear. OE and other aftermarket versions are made from lower strength, plain carbon steel. Sonnax heavy-duty reaction shaft kits are made from high-strength chromoly steel alloy to eliminate spline twist and spline wear. Contents include: * Reaction shaft with bushings * Reaction shaft-to-shell bearing * Reaction shaft-to-front carrier bearing * Shim

5.0 out of 5 stars ( 4 )

$217.22

Sonnax Servo Piston Kits

If you're looking for an easy upgrade to your automatic transmission, Sonnax Servo piston kits may be the answer. The improvement in shift quality is an immediate and noticeable value. These direct replacement kits will help to eliminate a bit of a "sloppy" gear performance caused by faulty OEM servo units. With all necessary rings and seals to prevent leakage and handle higher pressure, Sonnax servo pistons can be your link to greater band apply force. Choose the kit that matches your vehicle specs, then expect faster and firmer shifts!

4.77 out of 5 stars ( 30 )

$15.14

$352.46

Sonnax Extreme-Duty Clutch Hub and Intermediate Shaft Assemblies

The ideal upgrade for performance vehicles with the GM 6L80 or 6L90 transmission, Sonnax extreme-duty 4-5-6 clutch hub and intermediate shaft guarantees maximum protection against shaft breakage. The unique hub design improves oil flow and accepts Powerglide-style frictions to optimize clutch durability. In place of the 2-piece shaft/hub, Sonnax uses a much stronger, one-piece design that eliminates the OE assembly's weak, welded connection. It is custom forged from ultra-high-strength 300M billet steel, and then heat-treated and shot-peened for added durability. This combination of features guards against broken 4-5-6 hubs and the risk of rear splines shearing off.

Not Yet Reviewed

$1,015.08

$1,157.55

Sonnax 10-Clutch Drum Kits

Sonnax 10-clutch drum kits are optimized for Powerglide performance applications. Using the patented Sonnax 10-clutch drum system, the drum and piston accept 10 frictions and 10 Kolene steels, increasing lockup surface to allow significantly more torque than modified OE drums. The drum features a piston bore that is .060 in. deeper for greater piston travel. Kits include: * Complete 10-clutch drum kit with all related parts, including installed PTFE-coated bushing * Includes ten .060 in. frictions and ten .060 in. thick, 12-tooth Kolene steels * Excess material removed from high-strength, cast steel drum to reduce rotating mass * 6061 forged aluminum piston will not crack at high operating pressure like cast pistons * Forged chromoly steel clutch hub with lightening holes

5.0 out of 5 stars ( 1 )

$490.36

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