GMC Sierra Truck Bed Size & Dimensions

Knowing a vehicle’s size prevents you from encountering certain problems, such as fitting it in your garage. Are you wondering about the GMC Sierra’s bed size and dimensions. We've researched that concern for your convenience, and here’s what we found.

Take note that GMC Sierra truck bed sizes and dimensions often change throughout the years. For example, the 2013 model has a truck bed with dimensions of 69.3 x 62.5 x 21 inches. On the other hand, the 2021 Sierra's bed measurements were 69.90 x 81.20 x 75.50 inches..

Continue reading as we talk more about the different truck bed sizes and dimensions for GMC Sierras across different models. Also, stick around as we discuss other relevant yet important information about the GMC Sierra’s bed.

A pickup car with open trunk door ready for loading, GMC Sierra Truck Bed Size & Dimensions

What Are The Dimensions Of GMC Sierra Truck Beds?

Take note that GMC Sierra truck bed sizes and dimensions often change with each release. These measurements started altering since the truck’s first release in 1987.

 The GMC Sierra 1500 is available in a variety of models and exterior packages

Take a look at some of the GMC Sierra bed dimensions, particularly those from the 2013 to 2023 models:

  • 2013: 69.30 x 62.50 x 21 inches
  • 2014: 69.33 x 51.03 x 74.17 inches
  • 2015: 69.33 x 51.03 x 73.97 inches
  • 2016: 69.33 x 51.03 x 74.17 inches
  • 2017: 69.33 x 51.03 x 74.17 inches
  • 2018: 69.33 x 51.03 x 64.60 inches
  • 2019: 79.40 x 50.63 x 75.50 inches
  • 2020: 98.20 x 50.60 x 75.60 inches
  • 2021: 69.90 x 81.20 x 75.50 inches
  • 2022: 79.44 x 71.40 x 50.63 inches
  • 2023: 69.92 x 71.40 x 50.63 inches

Note: The measurements for the dimensions highlighted in this section are the length, width, and height. The recorded widths and heights start from the floor.

Bear in mind that the truck bed sizes mentioned in this section may differ for each trim variation of the different GMC Sierra models. Ask the truck manufacturer or your vehicle dealer if you need additional information regarding your options.

You can also read our post on trucks that have 72-inch beds if you’re looking for options with those cargo bay sizes.

Are Silverado And Sierra Beds Interchangeable?

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It’s possible to change the truck beds of Chevy Silverado and GMC Sierra trucks. However, certain elements need to be present for the change to go smoothly.

First, both the specific Silverado and Sierra models need to have short beds. Also, the beds need to have direct bolt-on designs.

Even if one of these trucks doesn't have those requirements, you can still swap their beds, but the process will be more laborious and time-consuming than usual.

How Do You Replace A Truck Bed On A GMC Sierra?

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If you want to replace your GMC Sierra’s bed, ensure that the new cargo bay’s dimensions are compatible with your vehicle’s specific model. Installing a truck bed that’s too small or too large for the vehicle’s frame may result in balance and weight issues.

Don’t forget to prepare yourself for this task by following the correct safety guidelines. Some of the preventive measures you need to follow are:

  • Wear safety clothing and equipment. Safety gear, such as protective goggles, mechanic’s gloves, and a dust mask, can help prevent irritation from handling certain materials.
  • Refer to your vehicle’s owner’s manual. Check the guide that should come with your GMC Sierra if you need help with certain aspects, such as the location of different parts.
  • Don’t smoke near your vehicle. Also, avoid placing flammable objects while working on your truck’s bed to prevent unwanted combustions and fires.
  • Tie up long hair. Otherwise, wear a cap or hat so that your hair won't snag or get caught in certain parts of the vehicle.
  • Place a warning sign near the work site. The sign should tell other people to stay away from the area as much as possible to help reduce the risks of accidents and injuries.

After completing the preparations, continue this procedure by following these steps:

What You’ll Need

  • Floor jack
  • Wheel chocks
  • Jack stands
  • Screwdriver set
  • Socket wrench set
  • Panel remover kit
  • Replacement GMC Sierra bed
  • Wooden boards (optional)

Step-By-Step Guide

Step #1: Remove The Old Bed

You can remove the old truck bed from your GMC Sierra using DIY techniques. But you can complete this particular step faster than expected by hiring a forklift service to remove the assembly.

You may ask your local junkyard for help. Also, you can ask the facility’s representative if you can dispose of the old truck bed immediately so you don’t have to bring it back home.

Still, if you want to complete this step using DIY methods, check out the video below for guidance:

Step #2: Remove The Rear Bumper And Tail Lights

Raise the GMC Sierra with the floor jack. Then, chock the grounded wheels to prevent the vehicle from rolling and/or sliding. Add jack stands to help hold the vehicle’s weight if the floor jack fails.

Remember to be careful when removing the rear bumper and tail light assemblies. So watch the following videos to help you complete this step with as little risk of errors as possible:

Step #3: Install The New Bed

First, get help of other people to help you with lifting and carrying the new truck bed. Don’t attempt to lift and carry the unit by yourself, even if you have the strength to hoist a load of about 200 pounds. A truck's cargo bay's dimensions often make it extremely difficult for one person to transport properly.

Use the help of others again when transferring the new truck bed from its rig to the rear of the GMC Sierra. You can also fashion a ramp or slide with wooden boards to make this easier for everyone.

Warning: Be careful when transferring the bed and laying it onto the truck. Mishandling this large component may result in imperfections, such as dings, dents, and scratches.

Step #4: Connect The Electronics And Reinstall The Removed Parts

Install the electronics on your new truck bed. Note that these electric devices may differ depending on your GMC Sierra’s specific model. One example is the Multi-Pro Tailgate found on certain Sierra models like the 2021 Elevation, SLT, and AT4.

Return the rear bumper and tail light assemblies to their original positions on the vehicle afterward. Don’t forget to test the electronics and tail lights after completing their reinstallation processes. That way, you can check for errors, allowing you to fix them promptly.

With the completion of this replacement job, you might also want to add accessories for your GMC Sierra’s bed. One item that may cross your mind is a retractable truck bed cover, which can help protect the cargo bay and its contents from harsh weather.

Check out this retractable truck bed cover on Amazon.

You can also watch this video if you want to learn additional details for this replacement procedure:

At this point, you might need help in choosing between a truck and an SUV for your next vehicle. If so, read our post highlighting that topic so you can learn the pros and cons of each choice.

Final Thoughts

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Knowing the different GMC Sierra truck bed sizes and dimensions can help you prevent fitting issues. Identifying and verifying these measurements can also help you complete certain tasks, such as replacing the vehicle’s old cargo bay.