How do you manually release the parking brake on a 1992 gmc sierra?

The 1992 GMC Sierra likely has a hand-operated parking brake, commonly called an emergency brake or e-brake. There's no "manual release" in the sense of a separate lever or button. To release it, you simply:

1. Make sure the vehicle is off.

2. Push down the parking brake lever. You'll likely feel resistance as the brake releases. If you're having trouble, you may need to rock the truck slightly back and forth to overcome any binding.

3. Confirm it's released. Try to slightly move the vehicle to ensure the parking brake is completely disengaged.

If the parking brake lever is stiff and difficult to release, it could be caused by:

* Adjustments: The cables may need adjustment. This is a more involved process that usually requires access underneath the vehicle.

* Frozen parts: In cold weather, components can freeze. Allow the vehicle to warm up.

* Worn or damaged parts: Worn cables, rusty mechanisms, or a seized cable can prevent release. This necessitates repairs.

If you are unable to release the parking brake after trying the above, you should seek professional assistance from a mechanic. Forcing it could damage components.