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Sonnax

4R44E 4R55E 5R44E 5R55E Boost Valve Kit Sonnax 37947-03K Large Ratio

4R44E 4R55E 5R44E 5R55E Boost Valve Kit Sonnax 37947-03K Large Ratio

Regular price $43.33 USD
Regular price Sale price $43.33 USD
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img{max-width:100%} 4R44E 4R55E 5R44E 5R55E Transmission Boost Valve Kit Sonnax 37947-03K Large RatioSome typical problems in 4R44E, 4R55E, 5R44E and 5R55E units are soft shifts, delayed reverse, poor modulator control and/or low line pressure in reverse. A worn boost valve is often the cause, allowing reverse and/or TV pressure to cross leak or exhaust. Sonnax offers two replacement boost valve kits for these units: the OE ratio kit 37947-01K and the increased ratio kit 37947-03K. The 37947-01K has OE spool ratios, to return line rise to stock condition. The 37947-03K assembly has increased ratios for slightly higher line pressures.Sleeves are manufactured from highly wear-resistant aluminum alloy.Valves are made from hard-anodized aluminum for better wear resistance.Tight tolerances restore the hydraulic integrity of the assembly.Kits improve engagement related to loss of boost oil and increased line rise in forward and reverse.Pressure Comparison Between OE and Increased Ratio Boost ValvesEPC PSI37947-01K(OE Ratio)37947-03K(Increased Ratio)LineReverseLineReverse3010713511414375178224194243120250313275343NoteOE sleeves may come in either a 3- or 2-circuit design. Boost valve kits37947-01K and 37947-03K may be used to replace either versionContentsValveSleeveParts ship daily from our distribution center.FREE SHIPPING on US OrdersIn a hurry - expedited shipping is available for this item GOT QUESTIONS on your specific Year/Make/Model?  Send us a message ¿Habla español? Escríbanos con el año, la marca, y el modelo de su vehículo. WARRANTY requests need to be accompanied with the appropriate code as 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 failures; for example valve body failures, internal wear or damaged hard parts.    Visit Our eBay Store: Phoenix Transmission Parts for all of your Automatic Transmission Part needs.
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