Transmission Switch

1972 GMC P25/P2500 Van 5.0L Eng VIN FSECTION Transmission Switch

Connect vacuum gauge in line to distributor vacuum advance unit. Put transmission in reverse on Hydra-Matic or high on manuals and Powerglide.

NOTE: Powerglide equipped vehicles must have rear wheels off floor and accelerated to permit shift into high gear.

Observe vacuum gauge for a manifold vacuum reading. Replace transmission switch if gauge has a "O" reading.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.