If your garage door makes an excessive amount of noise while opening, one of the first things you should check is the tightness of the opener drive chain. A loose, sloppy chain will slap against the T-rail, the central beam that provides support for the door trolley, and generate lots of noise as a consequence. In addition, a loose chain can also slip off the sprocket of the opener altogether, resulting in a non-working door. Tightening the chain is the logical solution, and it is a job that homeowners can perform easily. Below are the tools you will need as well as a step-by-step guide to tightening a loose garage door opener chain:

Tools and supplies needed

  • 8-inch adjustable wrench

  • Stepladder

  • Work gloves

Step-by-step procedure

1. Prepare your work space for safety - The task of tightening a loose garage door opener chain is simple and undemanding, but it can be dangerous if you don't prepare ahead of time. That is why the first step is to clear away an adequate amount of working space. First, remove any objects or debris that will prevent you from setting up your stepladder on a stable, smooth surface. Next, be sure the garage is well-lit; work during the daylight hours if at all possible to provide natural illumination. Finally, once the ladder is placed in a secure spot, close the garage door fully and unplug the opener motor from its outlet to prevent accidental activation while you are working.

2. Locate the trolley and identify its parts - After preparing the work area and unplugging the opener, locate the door trolley. The trolley rides on the T-rail and is attached to both ends of the door chain. Once you identify the trolley, note that the chain is attached to a stationary bracket at the end of the trolley closest to the door. The other end of the chain is attached to a bolt that is restrained by two nuts; these nuts are what controls the tension of the chain.

3. Check the tension of the chain - Before you begin adjusting the tension, it is a good idea to verify the chain is actually loose. To check the tension of the chain, place your head as close as possible to the rail and look down the length of the chain toward the opener. A properly tensioned chain should sag slightly but will not come close to dragging along the T-rail at any point during its length. At its lowest point, the chain should be no closer than approximately one-half of an inch from the rail; otherwise, it will need an adjustment. Lightly push down on the top of the chain to get a feel for its relative looseness and to help gauge an increase in tension later. Just be sure to wear work gloves, as the chain is probably covered in grease.

4. Tighten the chain using the tension nuts - After verifying the chain needs tightening, begin by turning the inside nut, which is the one closest to the opener, several turns in a counterclockwise direction when facing the door. This will cause the nut to back away from the door and toward the opener. Keeping turning until you open a gap of approximately one-fourth of an inch between the inside and outside nut.

Next, begin turning the outside nut closest to the door in a clockwise direction when facing the opener, and you will notice the gap you opened begin to shrink. This indicates you are pulling the opposite end of the chain closer, and the tension of the chain should increase as a result. You should be able to notice the increase in tension visibly as you sight along the chain; you will also feel the increased tightness when pushing down on the top of the chain. Keep turning the outside nut until it is completely tight against the inside nut.

5. Test your efforts - Once you have tightened the chain, plug the garage door opener back into its receptacle and test its operation. If you have tightened the chain properly, you should notice a dramatic reduction in noise and looseness of travel. However, if the chain is still loose, repeat these steps and tighten the chain further. Be careful not to over-tighten the chain, though. An overly tight chain puts excessive strain on the motor shaft and ball bearings, or the chain may break prematurely.