Garage Door Extension Springs 48" X 66" for 11' High Doors

Make your garage door safer and easier to operate with Extension Springs from North Shore Commercial Door, engineered specifically for 11-foot-tall overhead doors. These heavy-duty springs provide the proper counterbalance to support door weights between 100 and 300 pounds, reducing strain on the door and opener while ensuring smooth operation.

Each spring attaches to the horizontal track support via S-hooks and works in tandem with a safety cable and pulley assembly. As the door closes, the springs extend to absorb the load and slow descent. When opening, they retract to help lift the door, with initial spring tension holding it securely in the open position.

For safety and performance, two springs are required per door. Springs are sold individually and are color-coded by weight rating for easy selection.

Product Highlights:

• Designed for 11-foot-high overhead doors

• Provides proper counterbalance for safer door operation

• Springs sold individually (two required per door)

• Works with cable-and-sheave pulley systems

• Color-coded by door weight (100–300 lbs)

• High-quality steel for long service life

• Extends when door closes, retracts when opening

• Holds door securely in the open position

Selecting the Right Spring:

To choose the correct extension spring, you must know your door weight and height:

1. Disconnect opener power and lifting arm.

2. Clamp the bottom rollers with "C" clamps or vice grips.

3. Disconnect the springs from the track support.

4. Carefully lower the door by hand and weigh it using a scale.

5. Match the weight to the correct DASMA color code:

• 100 lbs – Tan

• 110 lbs – White

• 120 lbs – Green

• 130 lbs – Yellow

• 140 lbs – Blue

• 150 lbs – Red

• 160 lbs – Brown

• 170 lbs – Orange

• 180 lbs – Gold

• 190 lbs – Light Blue

• 200 lbs – Tan

• 210 lbs – White

• 220 lbs – Green

• 230 lbs – Yellow

• 240 lbs – Blue

• 250 lbs – Red

• 260 lbs – Brown

• 270 lbs – Orange

• 280 lbs – Gold

• 290 lbs – Light Blue

• 300 lbs – (varies by manufacturer code)

⚠️ Note: Springs are a safety-critical component. Always install in pairs and replace both springs at the same time for balance and performance.