What is the normal oil pressure on a 1987 2.9 liter Ford Ranger?

There's no single "normal" oil pressure for a 1987 Ford Ranger 2.9L. The acceptable range depends on engine temperature and RPM. However, a good general guideline is that at idle and operating temperature (around 200°F), you should see at least 10-15 PSI. As RPM increases, so should the oil pressure.

Crucially: You should consult your owner's manual for the *specific* oil pressure specifications for your particular engine. The manual will provide charts or ranges indicating acceptable pressure at different engine speeds and temperatures. This is far more reliable than a general internet answer.

If you're experiencing low oil pressure, don't ignore it. Low oil pressure can lead to serious engine damage. Check your oil level first, and if that's fine, investigate the cause of the low pressure with a qualified mechanic.