GM Service Manual Online
For 1990-2009 cars only

Your tachometer displays the engine speed in revolutions per minute (rpm). See "Grade Braking" under Tow/Haul Mode for more information.

Notice: If you operate your vehicle with the tachometer above 6,000 rpm, your vehicle could be damaged. The repairs would not be covered by your warranty. Do not operate the engine with the tachometer above 6,000 rpm.