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Chrysler
Line Pressure Booster45RFE, 545RFE
The Chrysler 45RFE, 545RFE and 68RFE use a full range line pressure sensor mounted on the outside of the transmission for "closed loop" line pressure control. Due to this system, traditional methods of raising line pressure by changing the PR spring or valves have no effect. Sonnax electronic line pressure booster kits alter the pressure signal sent to the computer, causing the computer to raise line pressure. Sonnax line pressure booster kit 44957-LB1 (68RFE) has 10-15 psi increase, and 44957-LB2 (45RFE, 545RFE) has 15-30 psi increase.
Higher line pressure increases clutch holding power and torque capacity, but with these transmissions, the increase has a limited effect on shift feel. Changes in shift feel will be noticed mostly under aggressive driving or loaded conditions. This part is ideal for heavy duty and modified vehicles and even stock transmissions when a little extra pressure is desired. No other modifications are required. The line pressure booster kit installs between the pressure sensor and vehicle harness using OE-style sealed connectors. Simply unplug the vehicle harness and reconnect with one of these parts.
The Chrysler 45RFE, 545RFE and 68RFE use a full range line pressure sensor mounted on the outside of the transmission for "closed loop" line pressure control. Due to this system, traditional methods of raising line pressure by changing the PR spring or valves have no effect. Sonnax electronic line pressure booster kits alter the pressure signal sent to the computer, causing the computer to raise line pressure. Sonnax line pressure booster kit 44957-LB1 (68RFE) has 10-15 psi increase, and 44957-LB2 (45RFE, 545RFE) has 15-30 psi increase.
Higher line pressure increases clutch holding power and torque capacity, but with these transmissions, the increase has a limited effect on shift feel. Changes in shift feel will be noticed mostly under aggressive driving or loaded conditions. This part is ideal for heavy duty and modified vehicles and even stock transmissions when a little extra pressure is desired. No other modifications are required. The line pressure booster kit installs between the pressure sensor and vehicle harness using OE-style sealed connectors. Simply unplug the vehicle harness and reconnect with one of these parts.
- Increased line pressure
- Increased clutch clamping force and torque capacity
- Installs on outside of transmission
- Easy plug and play installation
Affordable Kit for Big Performance without a Big Price Tag
The larger boost valves and stronger PR springs in Sonnax booster kits raise line pressure the SMART way by controlling pressure increase progressively with the demand of driving conditions.
- Simple, affordable parts require no special tools or reaming to install.
- Slightly stronger springs provide a modest base line pressure increase. Unlike other, stronger aftermarket springs, Sonnax springs won't overload the pump at idle.
- Larger boost valves deliver demand-based line rise without low-speed harshness. How Progressive Boost Works:
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The combination of Sonnax booster kit valves and springs gives you the best of both worlds: a modest pressure increase at the low end, with a high-end pressure that is equal to or greater than that of other aftermarket kit springs.
The combination of boost valves and springs is the ONLY way to progressively increase line pressure.
Product LineSonnax Line Pressure Booster Kits
BrandSONNAX
Package Height1.25
Package Width1.5
Package Length4.0
Weight0.08 PG
Part CategoryReplacement Parts
Vendor Part Number44957-LB2
Package Qty1
Package TypeEA
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Some parts are not legal for use in California or other states with similar laws / regulations
