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How to Tighten and Stop Tonneau Cover From Flapping?

For those with pickup trucks, tonneau covers not only protect the bed of the truck and keep your goods secure but also help you save money from low gas mileage. Using a tonneau cover can significantly reduce your gas charges when you calculate weekly. 

Tonneau comes in different styles, so there are various ways you can tighten and stop the cover from flapping. But how to tighten and stop tonneau cover from flapping? 

To stop your truck cover from flapping, you have to tighten the tension and adjust it according to the speed you are going in.

We’ll discuss this matter further here.


How Tight Should a Tonneau Cover Be?

Tonneau covers should be as tight as a drum. It has to be really close fitting with your truck. So, the cover you use has to fit the shape and size of your car.

If it is too tight, they might break or even tear. When too loose, they will flap or sag on a windy day, thus not providing their purpose. 

How can you know when your tonneau cover needs adjustment? If your tonneau cover is making noise while you are driving, it means it has not perfectly adjusted to the car or is not a perfect fit.

Moreover, there might be rainwater leakage onto the bed of your truck. And that could damage your cargo. 


How to Tighten a Tonneau Cover?

Tonneau covers have a tension block that secures it to your truck. By adjusting that, you can tighten it. Now, how will you know how much tight it needs to be?

When your truck has a roll-up tonneau cover, release the latch and roll it up. Below the surface, you will find the tension block on both sides and the clip to tune it.

Use the tension to adjust the tightness. To make your cover fit, turn both adjusters on two sides counterclockwise. 

If the above process does not adjust your cover the way you want it to, you may want to take a look at the bolts where you attached the tonneau to the rails. Readjusting the clamps may also help to tighten it.


How Do I Stop Tonneau Cover From Flapping?

Tonneau covers should definitely not be flapping or sagging in the wind. You have to fit it perfectly on both the driver’s and passenger’s sides to prevent it from getting any airflow. 

There may be extra tension knobs around your tonneau cover, usually found around the bed rails. And you can adjust these knobs alongside the ones underneath to stop the flapping.

If your tonneau is sagging, the gas mileage won’t improve, and your cargo will remain unsafe. However, if you have been using the same cover for years, it may also be time for it to be changed.

You could also use a solid one to stop the flapping that comes with the soft cover.


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Kevin Shaw

Editor-in-Chief at F150Lab

Kevin Shaw has a vast knowledge of pickup trucks, especially the Ford F150. He has been doing various DIY fixes, upgrades, and modifications to pickup trucks for more than five years now.

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