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Remember, transmissions have variations based on year, make, model and engine size, as well as for 2WD, AWD, 4x4, gas, diesel or hybrid and in some situations half years.  We encourage you to chat or call toll free with one of our knowledgeable staff members that will assist you in finding the correct part the first time and answer any questions you may have regarding parts for your build. Our goal simply put, is to get you moving with one order.

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5L40E 5L50E A5S390R A5S360R Transmission Boost Valve Kit Sonnax 55209-01K

Regular price $44.39 USD
Regular price Sale price $44.39 USD
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img{max-width:100%} 5L40E 5L50E A5S390R A5S360R Transmission Boost Valve Kit Sonnax 55209-01KWith Spacer, Large Ratio Vehicles with a 5L40-E transmission are prone to poor line rise or high reverse pressure problems causing poor shift quality and clutch failure due to leakage at the boost valve assembly. Sonnax offers two replacement boost assemblies: the 55209-01K with large ratio (higher line rise and firmer shifts) and the OE ratio 55209-04K¬†for factory performance.Boost valves are hard-coat anodized to eliminate wear on the inside diameter of the sleeves.Boost sleeves are made from alloy aluminum specifically designed to resist wear.Increased performance 55209-01K or OE ratio 55209-04K¬†assemblies are available.Kit salvages costly 5L40-E pumps.ContentsValveSleeveSpacerSpecsDia.: 0.531"Dia.: 0.432"Parts ship daily from our distribution center.FREE SHIPPING on US Orders In a hurry - expedited shipping is available for this item GOT QUESTIONS on your specific Year/Make/Model?Send us a message √ā¬ŅHabla espa√ɬĪol? Escr√ɬ≠banos con el a√ɬĪo, la marca, y el modelo de su veh√ɬ≠culo. This item is packaged for Wholesale Distribution¬†WARRANTY requests need to be accompanied with the appropriate codeas diagnosed by a professional transmission shop.Vehicles must be professionally diagnosed for solenoid failure prior to purchase.We cannot guarantee any one item will fix all transmission problems.Solenoid failure is often accompanied by additional failuresfor example valve body failures, internal wear or damaged hard parts. Visit our eBay Store: Phoenix Transmission Parts¬†For all of your Automatic Transmission Part needsCheck out my other items!Be sure to add me to your favorites list!¬†