Should I Use The Parking Brake On Automatic Transmission?

When It Makes Sense

• Good fit: Parking on an incline or decline where the vehicle’s parking pawl alone might slip, especially on older automatics with known parking‑pawl wear.
• Good fit: Leaving the car stationary for an extended period (e.g., overnight in a garage) where additional restraint reduces stress on the transmission’s parking mechanism.

When You Should Avoid It

• Warning sign: Parking on a perfectly level surface where the parking pawl already holds the vehicle securely; engaging the brake may be redundant.
• Warning sign: When the parking brake is known to be faulty or sticks, using it could cause the vehicle to move unexpectedly once released.

Pros and Cons

Pros

• Provides an additional mechanical lock, reducing reliance on the transmission’s internal parking pawl and potentially extending its service life.
• Improves safety on slopes, helping prevent unintended vehicle roll‑away, especially in manual‑wheel‑brake systems.

Cons

• If the parking brake is not fully released, it can place strain on the drivetrain or cause uneven tire wear.
• On some newer vehicles, the electronic parking brake may automatically engage/disengage, making manual use unnecessary and possibly interfering with system diagnostics.

Decision Checklist

• Is the vehicle parked on a slope or incline where the parking pawl might be insufficient?
• Is the parking brake functional and able to fully release without dragging?
• Does the owner’s manual recommend using the parking brake in conjunction with automatic “P” gear for your model?

Alternatives to Consider

Instead of relying on the parking brake, you can use wheel chocks on steep grades, engage the transmission in “Park” with a functional parking pawl, or employ automatic hill‑hold assist features if equipped. For vehicles with electronic parking brakes, follow the manufacturer’s push‑button sequence rather than a traditional foot pedal.

Final Recommendation

For most drivers, engaging the parking brake on an automatic transmission is a prudent extra precaution on slopes, during long stops, or when the transmission’s parking mechanism shows wear. On level ground and with a healthy parking brake, it is often unnecessary. Always consult the vehicle’s owner manual and, if unsure about the condition of your parking brake or transmission, seek advice from a qualified mechanic.