How To Install A Tonneau Cover With Bed Liner

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Last Updated on May 7, 2022

A bed liner protects your truck bed from any damage. We carry various freights in our trucks. Some of those can scratch or damage the truck bed itself. On the other hand, water and dust also damage the truck bed. A bed liner helps to protect our truck bed from all of these things.

People often think that it is pretty hard to install a tonneau cover with a bed liner. We assure you that it’s not that hard. We will tell you how to do that easily. Let’s first tell you the types of bed liners and what you’ll need to do before starting the installation process.

Types of Bed Liners and preparations

Bed mats and rugs only cover the floor of the truck’s bed. Bed mats are made with rubber and the rugs are made from polypropylene material. Materials and thickness are the main difference between these two. The spray-on bed liner is a protective coating of hard-wearing materials. None of these bed liners require any modification or preparations to install a tonneau cover.

On the other hand, drop-in bed liners require a little modification. This bed liner is generally a plastic cover made for your truck’s bed. It covers the sidewalls and sometimes the side rails of your truck bed. As all the tonneau cover sits on top of the side rails, you’ll need to trim the plastic over the side rails. If the bed liner only covers the sidewalls, making a few holes in the bed liner is enough.

How to cut or trim the bed liner:

As we have told you earlier, you’ll need to cut or trim your drop-in bed liner to install some tonneau covers. If you need to cut your bed mat or rug, using a good and sharp knife will do the job. If you have a drop-in bed liner that covers only the side walls. You should cut some holes using a drill for the clamps. You can also cut that portion of your bed liner using the following method.

To cut a drop-in bed liner you’ll need a measuring tape, a marker, and a reciprocating saw (with metal blades). If you don’t have a reciprocating saw, you can use a hacksaw (it’ll be a little harder though). You’ll need a tin snip to trim the bed liner. Follow the instructions below:

  • Now, take your tonneau cover’s side panels and put them over the side rails of your truck bed.
  • Measure the depth of the side rails of the tonneau cover with the measuring tape.
  • Mark the bed liner (where you need to cut it).
  • Take the reciprocating saw (or, hacksaw) and cut the bed liner. You should use a medium setting on the reciprocating saw and cut it carefully otherwise you can damage your truck bed.
  • After you are done with the cutting, take the tin snip and cut the edges (if there are any).

Install the Tonneau Cover

If you have read this far of the article, you have already completed the hard part of the total process. Installing most of the tonneau covers isn’t that hard. There are various types of tonneau covers. Different tonneau covers have different installation processes. Here, we will give you a generalized instruction that is applicable for all types of tonneau covers. Once you read the instructions, you’ll know what to do.

Necessary tools:

  • Wrench: to tighten the clamps/bolts
  • Screwdriver: to tighten the screws (if you have any on your tonneau cover)
  • Measuring tape
  • Drill (some hard tonneau covers require drilling)
  • An extra pair of helping hands if the tonneau cover is a hard type cover and heavy


  • Unpack the box of your tonneau cover and check if all the parts are delivered
  • If your tonneau cover requires a rubber seal on the sides or bulkhead side, attach the rubber seal first.
  • If you have a one-piece tonneau cover (usually they are hard-covers), just carry the tonneau cover and put it over the bed rails. Check all the sides and re-adjust perfectly. Attach all the clamps/bolts with the bed rails and you are good to go.
  • If your tonneau cover isn’t a one-piece, it’ll come with two side rails in the box. Put the side rails on each side over the truck’s bed rails. Check and adjust perfectly from the bulkhead and tailgate side. Use a measuring tape if required.
  • Attach the side rails with the bed rails using the clamps/bolts (all manufacturing companies provide them with the tonneau cover). Don’t tighten it all the way. You may need to re-adjust the side rails later.
  • Take the folded/rolled tonneau cover and put it over the installed side rails on the bulkhead side.
  • Attach the cover with the side rails using bolts/clamps.
  • Open the cover and unfold/unroll it and check if it locks on the tailgate side.
  • If not, you should re-adjust the side rails using a measuring tape. If yes, tighten all the clamps/bolts and screws and your installation is complete.

*Some tonneau covers require cutting a hole on the truck bed for the drain tube. You should follow the instructions provided with the tonneau cover. Or, you can check out our website.

How To Install A Tonneau Cover With Bed Liner

We have prepared this article to help you install a tonneau cover with bed liner. The instructions above are generalized for all types of tonneau covers. You’ll be able to install pretty much any type of tonneau cover by following these instructions. You can always take a professional’s help for this type of work. If you want to save some bucks or just want to do it for the fun this article will help you to do it yourself (DIY).

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Author: Charles King

Charles King is an automotive enthusiast with a keen interest in the latest technologies and products. He likes to educate himself and help other car lovers by sharing his knowledge. This website is a place for him to share his thoughts and experiences.

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