Availability
Summit Bucks
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
$999.99
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$1,205.99
Summit Bucks
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.
( 23 )
$124.13
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$282.02
Summit Bucks
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
( 11 )
$99.59
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$235.14
Summit Bucks
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.
( 108 )
$178.27
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$305.44
Summit Bucks
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.
( 21 )
$124.62
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
Summit Bucks
Sonnax heavy-duty automatic transmission output shafts allow energy to be absorbed via their torsional design, reducing peak power loads to critical areas. This, in turn, prevents shaft failure common in certain GM units. These steel output shafts are precision engineered and manufactured for unbeatable performance in high-horsepower street and strip builds. They're available in various lengths, and feature many unique refinements available only from Sonnax.
( 2 )
$722.91
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$774.01
Summit Bucks
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
( 6 )
$166.99
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$205.10
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 )
$217.22
Summit Bucks
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.
( 25 )
$91.85
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$292.41
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
( 1 )
$490.36
Summit Bucks
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.
( 20 )
$151.05
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$170.21
Summit Bucks
These Sonnax billet forward clutch pistons improve forward clutch piston strength and durability by using billet aluminum—and they're made with additional contours at points of high stress. These rebuild components can be used individually or with Sonnax input housing reinforcement sleeve kits. No alterations or fabrication is needed to use them in conjunction with aluminum overrun pistons. Sonnax billet forward clutch pistons can be used in both early and late model automatic transmissions, as noted in the application.
( 1 )
$96.28
Summit Bucks
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
( 1 )
$754.00
Sonnax case saver retainers are designed for 1999 and later GM 4L80-E units—and are the only intermediate clutch retaining ring case saver that allows the intermediate band to be retained. The case savers fit over the intermediate band anchor lug inside the case and extends rearward to support the intermediate clutch backing plate retaining ring, preventing case lug blow-out. Over the years there have been a variety of case saver designs, however, all required eliminating the intermediate band, as is often done in drag racing trans-brake applications. Only Sonnax case saver retainers support the intermediate clutch retaining ring yet are thin enough to allow the intermediate band to be installed to provide case lug protection in all applications.
( 5 )
$35.99
Sonnax Mustang flanged yokes are for the builders of Mustang driveshafts who want to upgrade from a 1330 U-joint. Those builders have long had to make due with purchasing an extra adapter flange to allow installation of a 1350 flange yoke. Now, with Sonnax flange yokes, the days of sourcing an extra adapter are over. Sonnax yokes are forged and precision-machined to accept a 1350 U-joint while maintaining compatibility with the OE 3.5 in. bolt circle.
( 4 )
$137.91
Sonnax pressure switch rebuild kits can help salvage your transmission electro-hydraulic control module (TEHCM), restore normal switch operation, eliminate codes, and provide renewed shift performance in all ranges. Some GM transmissions send various trouble codes related to internal fluid pressure failures to your TEHCM. These codes may be accompanied by torque converter clutch (TCC) apply problems or shift irregularities such as slipping, flares, harsh application, and bind-ups. Often, the cause is laminated portions of unobtainable OE pressure switches breaching, preventing normal switch operation. Avoid multiple breakdowns that can trigger failsafe mode and TEHCM replacement by ordering the Sonnax pressure switch rebuild kit recommended for your GM transmission.
Not Yet Reviewed
$94.90
Summit Bucks
Sonnax C ratio servo kits offer greater holding power, giving cleaner, firmer 1-2 and 2-3 shifts. They are machined from 6061 aluminum billet and feature lip seals on the piston for superior sealing over a wide range of fluid pressure. The C ratio servos are the largest in the C4 family, and will work equally well in performance C5 applications. The pins incorporate two PTFE sealing rings to insure the hydraulic integrity of the pins in worn cases. Experience firmer shifts with Sonnax C ratio servo kits. Kits include: * Piston * Cover with either purple anodized or machined finish * Servo pin with seal grooves * Gasket * Retaining ring * Spring * PTFE seals * Large and small lip seals
( 1 )
$224.07
Summit Bucks
Sonnax knows you want your transmission to shift like a dream. Their automatic transmission bands are extra-wide intermediate bands suitable for heavy-duty, commercial, and 4x4 vehicles. These drop-in replacements provide 15 percent more holding capacity and feature a 60 percent thicker case anchor, decreasing the chance of band failure under severe conditions. (Note: The red-lined version of these Alto bands is designed for high-torque street racing applications. The Kevlar®-lined version is too aggressive for street use and best suited for high performance racing applications.)
( 8 )
$46.93
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$267.47
Summit Bucks
Main shaft failure is a common problem in performance and heavy-duty GM TH400, 4L80-E and 4L85-E units. Sonnax replacement heavy-duty main shafts are manufactured from high-strength 300M with proprietary heat treatment and post heat-treat processing for exceptional performance, durability and value. These shafts are recommended for applications up to 1,000 hp. Additional details: * Advanced torsional design with spline and cross hole refinements for additional strength * Direct replacement for OE shafts
Not Yet Reviewed
$425.28
Summit Bucks
Broken clutch drum? Experiencing no forward engagement or slipping in 1st, 2nd, and 3rd gear? Sonnax Smart-Tech forward clutch drums offer the solution to restore proper gear engagement and hold. Their one-piece forged steel construction provides increased strength and durability over the OE-stamped drum. They also feature an increased groove depth to provide additional ring support.
( 6 )
$172.70
Summit Bucks
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
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$631.28
Summit Bucks
Sonnax 10-clutch drum, hub and piston 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. Sonnax 10-clutch drum, hub and piston kits include shims to make installation easy.
( 2 )
$191.36
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$494.00
Summit Bucks
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
$1,157.55
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