Does an 87 F150 have a low oil pressure cut off safety?

Yes, a 1987 Ford F-150 has a low oil pressure safety switch. While the exact implementation might vary slightly depending on the engine (e.g., 300 inline-6, 302 V8, 351 V8), they all incorporate a system that will illuminate a warning light on the dashboard and, in some cases, may even cut off power to the ignition to prevent catastrophic engine damage if oil pressure drops too low. The system usually doesn't instantly shut the engine down, but it gives a clear warning.