GlowShift 400 PSI Digital Transmission Pressure Gauge, 52mm

This is a 2-1/16 inch (52mm) electronic transmission pressure gauge that reads actual line pressure from 0 to 400 PSI off a dedicated sender, not a guess off the scan tool. You tap the sensor into a pressure port on the transmission (or an inline tee in the cooler line), run the harness to the cab, and the gauge shows you what the pump and pressure regulator are really doing under load. For anyone towing heavy or running a built trans behind a diesel, that reading is the early warning that a pressure problem is coming.

The kit is complete for a clean install: a 1/8-27 NPT pressure sensor, a 9-foot sensor harness, a 2-foot power harness, a gauge visor, mounting hardware and instructions. The digital LED face has 10 solid color modes plus 2 color-cycle modes and a tinted lens, and it self-calibrates at startup so the zero stays honest. It reads at a glance in daylight or at night.

What it catches on the bench and on the road: low line pressure from a worn pump or leaking valve body, a stuck pressure regulator, a failing pressure control solenoid, or pressure that drops off when the fluid gets hot. Watching pressure alongside temperature is how you find a slipping clutch pack before it cooks the fluid and glazes the frictions. Fits most automatics that have an accessible pressure test port; confirm your unit has a tap or plan to add an inline fitting.