Availability
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
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.
( 3 )
$855.99
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
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$770.64
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
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
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$1,113.02
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 )
$774.01
Sonnax offers a variety of extreme duty strength output shafts in different spline counts, as well as long and short lengths. All shafts can be purchased separately, with some shafts also available as part of complete extreme planetary assembly kits. These shafts are bolt-on for easy service and designed for use with different gear sets, depending on the application. Order the Sonnax extreme strength output shafts best suited for your application.
Not Yet Reviewed
$767.25
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$847.41
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