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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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$356.54
Summit Bucks
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
( 3 )
$563.04
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$582.46
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 )
$101.42
Summit Bucks
Wear at the piston pin bore surface can result in poor shift quality and burnt clutches and bands. Sonnax pinless accumulator piston kits prevent pin bore leakage. They're also longer to stabilize the piston and prevent piston cocking. They feature dual seals to stabilize and completely seal the bore, and steel balls to plug the existing pin bore. Fluid loss through the piston pin bore will no longer be an issue when you invest in Sonnax piston kits.
( 17 )
$8.94
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$10.86
Summit Bucks
Sonnax thrust bearings are replacements for your worn automatic transmission bearings to aid in smooth operation and noise reduction. The bearings act as a guide to help limit any axial movement which can hinder performance. Manufactured to exceed OE specifications for superior quality even under extreme conditions, order the Sonnax thrust bearings best suited for your application.
( 4 )
$11.20
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$18.47
Summit Bucks
Sonnax front endplay shims help solve the issue of too much front endplay. Whether it's due to various components wearing over time or the direct result of modifications—front endplay that has strayed from precise specifications can lead to costly repairs and/or replacements. Tighten things up to proper specifications with the set of Sonnax front endplay shims recommended for your transmission application.
Not Yet Reviewed
$7.39
Summit Bucks
Sticking of bypass components, spring relaxation, or poor ball seat in Ford 4R100 and E4OD units will allow the bypass to open at lower cracking pressure. This reduces TCC (Torque Converter Clutch) apply pressure, cooler flow at the overdrive section, and radiator flow responsible for heat transfer. Sonnax automatic transmission cooler bypass valve kits allow the bypass valve assembly to be rebuilt, salvaging the OE fittings and maintaining cracking pressure at 70 to 75 psi. Features: * Hardened steel T-valve provides secure check ball seat and adequate bypass flow * New spring cracks open at 70 to 75 psi to provide lube if cooler is blocked or restricted * Hardened alloy steel check ball resists damage * Seven new O-rings provide positive seal for cooler circuit * Drop-in Zip Valve parts install quickly and easily Contents: * T-valve * Spring * Check ball * O-rings -- One small -- Two medium -- Two large -- Two extra-large
( 1 )
$16.74
Summit Bucks
The Chrysler 46RH/RE, 47RH/RE, 48RE and A727 units used in high performance applications often bend or break the kickdown band strut. To help eliminate these issues, Sonnax offers heavy-duty kickdown band struts—made of solid, heat-treated steel that will not bend or break like other stamped struts. These quality replacements feature an extra-thick cross-section for maximum toughness to withstand the increased intermediate "band" applied forces that are common in high performance applications. Installation is easy: just remove the pan and valve body to expose the bottom of the transmission, loosen the adjusting screw to remove all tension from the band, then remove the original strut and insert your new one with the flat surface facing away from the band. Tighten the adjusting screw to manufacturer specs—and you're good to go!
( 5 )
$19.68
Summit Bucks
Transmission cases made in 1994 and 1995 have neutral safety switch mounting holes, but do not have the top mount shifter bracket holes. That's where these Sonnax shift cable mount brackets come into play, by allowing installation of the 1994 and 1995 transmissions or cases into 1996–97 vehicles that originally had case mounted shifter brackets. Additionally, if a late case has become damaged or has broken top mount bosses, these Sonnax shift cable mounting brackets can be used as an alternative to allow you to correctly mount the shifter cable and allow the reuse of the case.
( 1 )
$18.99
Summit Bucks
The OE pressure regulator valve design prevents adequate cooler flow at low rpm and high-pressure conditions, which can create overheating. Additionally, in 1999 and later vehicles, the factory EPC pressure was set high at idle, resulting in engine surge conditions in GM 4L80-E and 4L85-E units. Sonnax lube-regulated pressure regulator valves provide a significant increase in cooler flow under low rpm and high-pressure conditions that benefits all vehicles—and eliminates the need for reprogramming 1999 and later vehicles with high EPC pressure at idle.
( 20 )
$39.30
Summit Bucks
Noticing some forward slip and/or delayed engagement with your GM automatic transmission? Sonnax accumulator pistons are direct replacements for OE plastic pistons and restore sealing integrity at the pin bore. The aforementioned issues, as well as burnt clutches and bands can be caused by loss of fluid. Deterioration at older aluminum piston pin bores due to repeated reciprocation and/or cracks in plastic accumulator pistons may be the cause. Avoid a costly valve body replacement by ordering a Sonnax accumulator piston.
( 2 )
$7.91
Summit Bucks
Sonnax return springs are available in a variety of styles to assist in your automatic transmission rebuild. Replacement part types include high clutch return springs, pump slide springs, detent springs, reverse clutch return springs, and more. They're machined from quality materials for long-lasting performance, and can be ordered individually or in larger quantities. Select the springs required for your specific transmission application.
( 4 )
$7.98
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