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.
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.
Check out these other great Sonnax transmission kits:
We used the 4T65E-LB1 in several applications...it doesn't give harsh shifts, just a little something extra. Very nice product and I highly recommend it."
Pine Bluff, AZ
Use the Sonnax 4L60E-LB1 progressive boost valve...it will put a smile on your customer's face."
Dan's Service Center
I just received my line pressure booster for my 2012 Ram and wow! The CPU gets the new pressure signal very fast...30 seconds of slow-medium driving...and when I floor it....yihaaa! It shifts aggressively and I can feel the tranny grab the clutches with more power when it changes gear...great product! Thumbs up!!!"
Senneterre, Québec, Canada
Sonnax electronic line pressure booster kits modify the sensor signal which causes the computer to create a pressure increase. The booster kits 44957-LB1 (10-15 psi increase) and 44957-LB2 (15-30 psi increase) are installed between the pressure sensor and vehicle harness using OE-style sealed connectors and do not require any modification or changes to the transmission. Simply unplug the vehicle harness and reconnect with one of these kits in line.
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