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45RFE, 545RFE, 65RFE, 66RFE, 68RFE

Line Pressure Booster Kit
Part No. RFE-LB1

Fits gas and diesel units.

View Instructions

Chrysler RFE transmissions have a unique, full range pressure transducer and real-time adaptive closed-loop pressure control system. Because of this, it is not possible to raise pressure in an RFE the same way you would in other transmissions. The typical method of installing a stronger pressure regulator spring or larger boost valve will not work because the RFE control module will simply adapt and return pressure to OE specification. An electrical booster option is the only way to raise pressure on an RFE.

Sonnax line pressure booster kit RFE-LB1 is an improved design over a simple resistor circuit. Featuring an integrated chip (IC) circuit and a stronger pressure regulator spring, this new kit delivers 10 psi increase at lower pressure range and 25 psi increase at higher pressure ranges. Only Sonnax line pressure booster kits provide progressive pressure increase which gives you smooth engagements and lower load on the pump at idle, but a greater increase in pressure as the transmission is worked harder. To find out more about how the kits work, and what results you can expect, see Achieving a Progressive Pressure Boost in RFEs.

This kit is ideal for heavy duty and modified vehicles and even stock transmissions when a little extra pressure is desired.

  • Achieve shorter shifts and increased torque capacity without creating low-speed harshness
  • Improved clutch holding capacity for increased durability
  • Progressive pressure increase as driving conditions become more demanding
  • One kit fits both gas and diesel applications
  • Pressure Regulator Spring
  • Wiring Harness with Connectors

April 05, 2016

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  • Rfe lb1

Sonnax Line Pressure Booster Kits

Peace of mind for everyday customers pushing vehicles to the limit

Sonnax booster kit components are uniquely designed for precision pressure control. At low-end pressures, they deliver normal engagements, normal light throttle shifts and smooth coastdown shifts. When vehicles are pushed harder, components progressively increase pressure for improved clutch holding capacity and increased durability.

Learn more about Line Pressure Booster Kits