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Filter Minder® Visual / Electrical Switches

Filter Minder® Graduated Switch

Air Filter Restriction Monitoring Gauge / Switch

Graduated / Electrical Indication / Threaded Mount

How It Works

A combination graduated indicator and switch, the Filter Minder® Graduated Switch features a position indicator that progressively fills the window as air filter restriction increases, locking at the highest restriction. When it reaches the red zone, or highest recommended restriction, it sends a signal to the filter warning light on the dash or to the engine computer to record as a diagnostics fault. The warning light locks on until the indicator is reset.

The Filter Minder® should be reset whenever the service indicator is checked to determine air filter restriction or when a new air filter is installed. Push the reset button at the end of the service indicator, and the position indicator will return to zero.

Filter Minder® Graduated Switch Indicator


135578 (1/8-27 NPT)
136578 (3/8-24 Straight Thread O-Ring)
137578 (M10x1 Straight Thread )-Ring)


Mounts directly to air cleaner or air induction piping.  Adaptor fittings are available.  Brackets for remote mounting are also available.  See Accessories / Related Products.


  • Vacuum Indicator
  • Locking Type
  • Operating Temperature: -40 to +250°F (-40 to +121°C)
  • Switch Activation Point: 8" water vacuum (2kPa) minimum to 35" water vacuum (8.7kPa) maximum. Contact the company for special calibrations.
  • Accuracy: ±10% at switch activation
  • Material: Polycarbonate housing
  • Normally open or closed switches with precious metal contacts
  • Molded in Packard Metri-Pak 150 Series
  • Severe Dust Filter also available


  • Length: 3.1" (79mm)
  • Diameter: 2.0" (50mm)  [64 mmwith connector]

A Few of Many Industries Served

Air Filtration Markets Served


  • Integrated switch that can be configured normally open or closed

  • Durable, heavy-duty design

  • Private labeling available

  • Multiple mounting configurations

  • Resistant to under-hood chemicals


  • Opens or closes a switch at highest set point which provides a signal to the control module or light

  • Shows exact level of air filter restriction

  • Maintains last recorded level of full-engine-load filter restriction

  • Reduces down time and aids in maintenance planning

  • Helps with troubleshooting low power

  • Helps prevent excess fuel consumption due to a restricted filter