* At idle (around 600-800 RPM): You should see at least 10-15 PSI. Some slight variation is normal depending on oil temperature.
* At operating temperature and higher RPM (e.g., 2000 RPM): You should see 30-40 PSI or higher.
Crucially, consult your owner's manual. It will have the most accurate and specific oil pressure specifications for your particular Trailblazer's engine (it likely has either a 4.2L inline 6-cylinder or a 5.3L V8). The manual will likely provide a chart showing the expected pressure range at different engine speeds and temperatures.
If your oil pressure is consistently outside these ranges, especially if it's low, it's crucial to have your vehicle inspected by a mechanic immediately. Low oil pressure can cause serious engine damage.
