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Over The Rail vs Under The Rail Bed Liner

Over The Rail vs Under The Rail Bed Liner

Many people select a bed liner for their truck that is durable and good quality. In addition, they add more value to the pickup trucks by protecting them from damage.

It is better to choose bed liners that prevent skidding and rusting of the vehicle’s inner side. These protect the pickup surface and ensure the safety of the cargo by keeping it in its place.

Over the rail bed liners are present on the truck’s interior surface and over the truck rails. These bed liners add an extra layer of protection from UV rays and are suitable for daily use. However, these are expensive, fade quickly, and are prone to damage by sharp objects due to the thin layer. Under the rail bed liners are present under the rails and are easy to install inside the vehicle. So, over the rail bed liners are of good quality, highly durable, and airtight. While under the rail bed liners are easy to install and budget-friendly. 

The choice of bed liners depends on the requirement of the truck owner for the vehicle and its specific use.

Keep the purpose of installation in mind, and read about over the rail and under the rail bed liners. 

Over The Rail vs Under The Rail Bed Liner

Different bed liners have their benefits and disadvantages according to texture, price, and durability. Furthermore, some of them fit tightly to the truck surface, but some attach loosely.

The difference in quality and the lower cost can be the reason behind choosing a protective liner for your vehicle. 


Over the rail

Under the rail


High quality

Poor quality





Expensive ($400 to $700)

Affordable ($100 to $200)


More prone to dents and scratches

Less prone to damage by dents and scratches













Dampens sound



I surveyed 918 truck owners to know about their preference for bed liners, whether they choose over the rail or under the rail bed liner.

Out of 918 people, 615 people (67%) said that they prefer to install over the rail liners to their pickup beds because of their high durability and tight-fitting.

While 201 people (22%) said they select under the rail bed liners because they want to add truck caps to secure the cargo.

 The remaining 102 people (11%) said that both bed liners are good and would prefer to choose according to their requirements.

What are over the rail bed liners?

The bed liners that are wrapping the steel on the truck rails or cover the rails directly are over the rail bed liners. Therefore, they are present above the surface of steel lips and protect them adequately.

Furthermore, these bed liners protect the sides of the truck bed from scratches. It also prevents damage to the interior surface and covers the sides and rails.

Why would you use over the rail bed liner?

Over the rail bed liners provide multiple benefits to the users that make them ideal to use. It can protect the vehicle better and make it suitable for hard work like frequent loading of heavy objects.

An extra layer of protection 

These bed liners add an extra layer of protection to the rails and bed surface. It functions like a barrier between the metal surface and the environment.

It prevents direct exposure of the truck bed to sunlight and reduces the negative impact of UV rays. In addition, it keeps the surface clean when chemical spilling occurs during loading the cargo.

Suitable for daily use

It is better to install a bed liner over the rail when the pickup is excessively used.

There is a reduction in damage to the bed due to the presence of a high-density polyurethane plastic in between the metal and heavy load.

Prevent skidding

It attaches firmly to the surface of the truck and the rails. As a result, it prevents skidding on the bed surface while loading heavy objects on the pickup bed.

In addition, it helps maintain a firm grip on the floor so that you cannot slip.


Furthermore, applying a spray liner on the bed surface provides a very fine or thin coat that is tricky. 

You can spray it on the truck surface after cleaning and washing it for a smooth texture. It fits tightly and does not allow air to enter it.

Restricts airflow 

The tight-fitting of over the rail liner protects the metal surface efficiently by restricting the airflow inside. It does not allow elements in the air to reach the truck floor and damage it.

Prevent rust

In addition, it does not allow moisture to reach the bed surface. This way, it prevents rusting by limiting the exposure of metal surfaces to air and water.

Disadvantages of over the rail bed liners

Over the rail liners can be bad for some reasons, like high cost. Moreover, it is more prone to damage like dents and fades quickly.


It is expensive to install these liners because it increases the cost of bed liners for applying not only on the bed surface but on the rails also. It requires almost $400 to $700 for installation.

Prone to damage

These are more prone to damage as it is present as a thin layer on the surface. In addition, it can get scratches and dents on the surface due to the loading of sharp and heavy objects.

Quick fading

One more drawback of applying bed liners over the rails is the quick fading of the color due to exposure to sunlight.

What are under the rail bed liners?

The bed liners present only on the truck bed and adequately fit the interior surface are under the rail bed liners. You can drop them in the truck bed by getting a polyethylene plastic custom-fit covering.

Additionally, they move along the sides of the truck bed but stop before reaching the rails. Finally, it allows you to add accessories over the bed, like canopies or tonneau covers.

The edges of the truck bed or rails do not contain any liner and allow you to use this painted surface for adding top accessories.

Why would you use under the rail bed liners?

You can get many benefits by applying under the rail liners. Under the rail bed liners are affordable to add a layer of protection and are highly resistant to chemical spilling.

Cost-effective and easy installation

It does not require any expertise and the drilling of holes to install an under the rail bed liner. You can place the plastic covering on the surface by dropping it inside the vehicle.

Furthermore, these bed liners are budget-friendly, and you can purchase them for $100 to $200.

Resistant to chemical and oil spillage

The thick and tough layer under the rail liners provides resistance to chemical spills. As a result, the oils and chemicals cannot cross the plastic barrier to reach the metal surface.

Protection from scratches

Moreover, these are made of tough plastic material that protects the bed surface from long-term scratches. It can handle the high load impact effectively due to its tough texture.

Ideal for truck caps

These are perfect for adding canopies over the bed surface. In addition, a clean metal surface having no bed liner provides a suitable place to attach the truck caps.

Interconvertible and removable

In addition, these bed liners are interconvertible and allow you to add the truck caps on the rails later on. 

Disadvantages of under the rail bed liners

There are some disadvantages of under the rail bed liners with its multiple advantages like no reduction in noise, skidding, and rusting due to loose-fitting to the truck surface.

Rusting of the truck bed

One of the main disadvantages of applying under the rail bed liners is that it can result in rust formation on the metal bed.

It exposes the metal surface to air, and moisture allows the reaction of oxygen and water with the metal and causes rusting.


In addition, there is a loose attachment between the liner and the inner surface that shows its temporary attachment.

The quick installation of under the rail liners can be responsible for skidding.

It displaces from the pickup surface, resulting in slipping when you are loading the cargo on the bed.

No noise reduction 

Furthermore, it cannot dampen the sound produced by the vibrations in the truck when it is moving on the road.

A truck bed liner can reduce the noise when it fits tightly to the surface and attaches permanently to the surface, but under the rail liners are removable and attach temporarily.

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