March 09, 2015
This content relates to two discontinued Sonnax parts: pressure regulator valve kit 104520-14K and oversized pressure regulator and boost valve kit 104520-07K. These kits required drilling the pump, and Sonnax now offers equally effective repair options that eliminate that extra labor: drop-in kit 104520-15K and oversized kit 104520-16K.
The best way to address GM 6L45, 6L50, 6L80, 6L90 pressure regulator valve problems is by replacing a wear-prone OE valve with an improved Sonnax drop-in Zip Valve™ or oversized part. Installation does require drilling a small hole in the pump, though, to prevent excessive line pressure. Learn more about why drilling is necessary and watch the simple, step-by-step process in this quick video.
March 09, 2015
March 09, 2021
Andrew Jessiman
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Jim Mobley
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