How To Install a Sliding Window In a Truck (DIY Guide)

If the sliding window in your truck isn’t sliding like it used to, or you wish that your stationary window would let a little breeze in, you came to the right place. It sounds like you could benefit from installing a new sliding window in your truck. In this guide, I’ll walk you through the whole process and I’ll answer a ton of questions along the way.

The short version of the installation misses a lot of the details but will give you a good baseline. Start by removing your current window. Buy a new window that will perfectly fit in your truck’s window frame. Buy a new gasket or urethane, depending on which your truck calls for. Apply either option to your new sliding window and clean/ prepare the window frame of your truck. Complete the installation and give it a nice clean with Windex.

I’ll show you how to install a sliding window using urethane as well as a rubber gasket, depending on your truck. I put the instructions in two different step-by-step guides at the bottom of this article.

What Is a Sliding Window?

A sliding window is unique to just pickup trucks. It’s a long window that is sectioned off in the middle. The glass is cut into sections that can slide over one another, effectively opening the window.

The style of a sliding window really depends. Sometimes it’s a little doggy-door size sliding piece, and other times the whole height of the glass slides a certain distance.

Since the rear window of a truck doesn’t typically roll down (called a “Breezer window”) or hinge open, the only way to get fresh air is with a sliding window. For reference, a lot of trucks have a stationary piece of glass at the rear.

Where the Window is Going to Go

This guide is all about installing a sliding glass window in your truck. If you didn’t know, the window goes in the rear of your truck cab.

People will often do this installation if they currently have a solid, unmoving piece of glass in this slot and they want to upgrade to a sliding one.

If you look at your truck from the rear, you’ll see the glass as well as the frame that it sits in. There’s a recessed piece that goes beyond your truck’s body, and that’s where the window will sit.

It’s recessed so that the rear is flush after installing the window.

The Importance of Picking the Right Window

My step-by-step guide is assuming that you already have a sliding window on-hand. There’s no realistic way to change a regular windowpane into a sliding glass window on your own.

Luckily, there are a number of sources that sell a sliding window in a box. It’s a matter of doing a quick search, plugging in the year, make, and model of your truck, then finding the perfect window.

A place like Gordon Glass Co. is a good place to start. I’m not affiliated with them at all, but my buddy used them for a previous sliding window install and it worked out really well.

Amazon also sells sliding windows for a select amount of vehicles. Below is a sliding window you can purchase directly on their site, this one is specific for select Ford pickup trucks but you can choose other makes and models.

NAGD OEM Heated Sliding Back Window Glass Back Power Slider Compatible with Ford F150 Pickup 2004-2014 Models

The simple fact is that it’s very important to pick a window that fits. If the curvature is different or any dimensions don’t match up perfectly, the installation isn’t going to work.

This whole install is contingent on the surface of the window matching up perfectly with the surface of the frame in your truck.

If you install a “close enough” option, a few things can happen. The worst outcome is that the glass can become loose and fall off over time. The more common issue is that there will be a draft as you’re driving, you’ll hear rattling, and the road noise will be much louder. Your cab won’t be as insulated against outside temperatures, and there will be a rain leak where the rear window is.

This installation doesn’t have a lot of adjustment after you complete it. The only way to change out the window is to repeat the entire process, wasting your time and money.

This Works if You Currently Have a Sliding Window or Not

I just want to give a heads up. This process will work if you have a dysfunctional sliding window currently, or just a solid piece of glass (no sliding window). A big part of the process involves a removal, so it really doesn’t matter what used to be there.

In other words, you can upgrade to a sliding glass window or replace yours using the same steps.

How Long Should it Take?

For a first-timer, the whole process can be done in an afternoon. There’s nothing super technical about the process, and you don’t need any specialized tools or experience. Take it slow and make sure you’re patient during the process to get the best results.

After all, it’s not easy to undo the install after it’s all done. You’ll need to make all changes prior to sticking the window to the truck in the last few steps.

If you have a lot of experience doing this, then it can easily be done within an hour with two people on the job.

Before Continuing, Which Window Type Do You Have?

There are two distinct types of rear windows in trucks. Your window is either set using urethane or a gasket. Both processes are different, so I built two different guides (the following two sections).

Before continuing, you need to understand which guide to use. Look at your window from the exterior. If you see thick rubber going all around it, then your window uses a gasket. If it looks like the glass is just floating there, then there’s urethane holding it in place.

Step 1: Cut the Urethane

There’s a good chance that your current window has urethane to keep it in place. This is a compound that adheres materials together on a molecular level — like a fancy, engineered super glue.

The urethane is there to ensure your glass doesn’t come out and it also keeps air from coming in around the perimeter of the window’s panel.

To cut it out, you have a few options.

Using a Wire Tool

The pros will use a wire tool. This is a thin wire that can be fed between the glass and urethane, separating the two. You start by feeding it through the top of the glass from the interior. Fold the wire in half and use a pry or driver to push it fully through the bead of urethane.

This can also be done with piano wire or any sturdy fiber that you have laying around.

Once the wire is all the way through, straighten it out. Grab both ends and spin them around separate handles so you can get a better grip. Use a sawing motion while you move the wire across the whole perimeter of the glass.

Using a Screwdriver or Chisel

If you don’t have one of these tools, then you can use a flathead screwdriver or thin chisel and some patience. The process is the same. You want to chisel away at the urethane all the way around the truck’s glass.

With this method, you need to be really careful. You don’t want to crack your glass during this process and that’s easier to do with this DIY method.

Using a Glass Removal Tool

The final option is to use a window remover tool. This is an angled blade that will cut the urethane bead out without damaging the glass. You should use it from the exterior of the truck so you can get better results.

Again, you should use this tool to cut along the perimeter of the glass.

Step 2: Razor Blading the Remaining Urethane

After going through the first step, there’s still a chance that there is leftover urethane keeping your window in place.

Rather than grabbing one of the tools used in the previous section, you should use a razor blade instead. From the interior of the truck, pinpoint the areas that are still stuck. You can do this by standing in the interior and pushing on the glass in different areas, seeing which spots won’t budge.

Use the razor blade to carefully slice away the urethane and any other obstructions.

Step 3: Remove the Glass

Now, the rear piece of glass should be able to be removed. Remember that you’ll need to push from the interior to remove it (in other words, the glass will be removed away from the cab of the truck).

If it’s not coming out, go through steps 1 and 2 again to pinpoint the issue and remove it.

Step 4: Clean the Frame

Once removed, take a look at the frame from the exterior of your truck. You’ll probably notice a number of things cluttering up this space.

For one, you’ll have residual urethane. You should also find a combination of rubber, dirt, and dust. To remove the urethane and rubber, utilize your chisel or razor blade. However, you don’t want to remove ALL of the material. You need a very thin layer to be on the frame for the rest of the installation to work.

For the following sections, you’ll need this area to be flat, smooth, and clean. Grab a towel and wipe away the excess dirt and debris.

Grab another towel and use some soapy water to give this frame a thorough cleaning. Dry it with a third towel to complete the process.

Step 5: Source and Dry Fit Your New Sliding Window

As far as DIYing goes, it’s not an option to make your own sliding window. Cutting glass and framing it in place takes professional equipment and expertise. For this step, you’ll have to start with a purchased sliding window.

Alternatively, you can grab a sliding window from a junkyard if you see one intact on a comparable truck.

If you want my advice, I’d go for a brand-new, purchased sliding window. You’ll get more life out of it, and you already know that it works perfectly without any drafts or rattling.

Take the sliding window out of the box or whatever packaging it came in. Do a quick dry fit to make sure it fits. To do this, hold it against the rear window frame of your truck without adhering it to anything. Check for large gaps around the window or anything that would prevent you from using it.

This also includes making sure the whole urethane pad will be in contact with your frame. If the arc of your window doesn’t match the arc of your truck’s window frame, then you can’t go any further. You’ll need to source a window that fits better before continuing.

Step 6: Prep the Sliding Window

Here’s a quick chemistry lesson on how urethanes work: they start out as a liquid. The liquid seeps onto both surfaces that come in contact with it. Over time, the liquid will go into any surface defects, cracks, and bumps on both surfaces.

As the urethane cools and hardens, it creates a chemical bond between both surfaces.

The more surface defects you can create, the better the adhesion will be. Using urethane on two, molecularly smooth surfaces actually won’t work at all. You can just pull the pieces apart.

To get a better bond, an abrasive like a Scotch-Brite pad will work wonders. It scuffs up the trim on your new sliding window without doing any damage.

In this step, grab a Scotch-Brite pad and work the bonding surface where the sliding window will be installed, not on the glass itself of course.

The bonding surface is the exterior perimeter of the sliding window. More specifically, it’s on the part that will be facing the cab, not facing the tailgate. The bonding surface will either be flat or curved along with the window.

It’s called the bonding surface because this is where the urethane will ultimately go, bonding the window to your truck.

Use a side-to-side motion as opposed to a circular motion. This step will also get rid of any surface contaminants from the manufacturer or shipping container, resulting in an even better bond.

Use a fresh towel on your sliding window bonding surface to get rid of any final pieces of loose contamination from the scuffing process you just did.

Your window is now ready for installation.

Step 7: Add the Urethane

Start by picking out your urethane. You want something primer-less that can be used on auto glass and acts as a sealant.

In the past, I’ve used Dow U-418 Auto Glass Sealant

Take the automotive urethane tube and put it into a caulk gun. Cut a V-notch in the top so you can lay a single bead as opposed to smearing a layer on the window.

You can either put the urethane on the window or the frame itself. Personally, I’ll say that it’s easier to do it on the window. Why? You can use a flat surface like a table or sawhorse to prop the window and keep it flat. Then you can really take your time applying the urethane.

If you try to apply it on the frame instead, gravity is going to be fighting you. The bead can start to sag or drip and will result in a less clean-looking window.

Be very methodical about how you lay this bead. Ideally, you will have a single, perfect bead going around the center of the bonding surface of the sliding window, all the way around. With a caulk gun, this requires taking pauses and multiple pulls of the trigger.

Before laying the bead, grab a piece of scrap cardboard. Practice your beadwork before doing it for real on the window.

A bead is the best geometry for urethane. When you compress the window into the frame, it will flatten out symmetrically and make the best bonding configuration for your window.

It also prevents you from overdoing it and spilling urethane out of the bonding surface. Too much urethane means the excess will drop down and could permanently muddy up your window.

KEEP IN MIND this bead is only going along the bonding surface. Do not put any urethane alongside the center framework for the actual sliding piece of the window.

Step 8: Install the Window

This might be the most important part of the process. I would suggest getting a buddy or two to help out. One person should be positioned on either side of the truck, and the third can be sitting in the bed, near the window.

You should wear some disposable gloves in case you brush against the urethane (it’s a pain to wash out of your hands, trust me). I also recommend suction cups to increase the grip on the sliding window when installing.

IMT 2 Pack 8″ Glass Suction Cup Heavy Duty Hand-held Vacuum Panel Lifter

Very carefully position the window in front of the frame. Slowly set the bottom in position on the frame before rotating the window and placing the top against the frame as well.

With the full window in position, it might help to put two or three pieces of glass tape on the top of your truck, connecting to the glass. This will allow you to make minor adjustments before finishing the project.

The minor adjustments would entail shifting around the sliding window. You want there to be an even gap all the way around the window. If you noticed it’s uneven, then you should adjust it as soon as possible. Once the urethane cures, there’s no way to change your placement without repeating all of these steps and installing it again.

When you’re happy with the position of it, you’ll want to apply firm pressure against the window, pushing it into the frame. Go around the full perimeter and push down every few inches.

Step 9: Completing the Install

Some sliding windows have tabs on the interior face. These tabs get pulled down and hold onto the surrounding framework of your window. If you noticed tabs on your window, spend this time to pull back your truck’s trim and push the tabs into these gaps all the way around your window.

The urethane will dry within a few hours. Check the tube to get the exact time for the specific urethane you used.

During this time, don’t touch the window at all.

For the next few days, you should avoid the carwash, so you don’t disturb your new window.

You should take some time to make sure the window moves correctly and you’re happy with how it looks. If you like it, then use a little Windex and clean the glass from the interior and exterior of your truck. Be careful not to get any Windex on your car’s paint.

Step 1: Remove the Window

You need to start by removing the window. For this removal, you can just use a flathead screwdriver. Use it to pry one corner loose. You can do so by wedging the screwdriver between the rubber and metal of your truck. Use a chisel or spackle knife to keep the wedge open as you work across the top perimeter of your truck’s window with the screwdriver.

While doing this, a helper can apply a little pressure on the window from the interior to separate the gasket from its channel.

After removing enough of the gasket, pressure from the interior will pop the window out of its frame. Make sure you’re ready to catch the window so it doesn’t flip backward into your truck’s bed.

Step 2: Remove the Gasket

Lay the window down on a flat surface and remove the entire gasket. It probably has a U-channel or V-groove for the glass to sit in, and removal is as simple as pulling the rubber away from the glass.

Take some time to closely look at the gasket. If there is any level of damage, then you’ll need to get a replacement gasket before continuing.

If it’s in good shape and just dirty, you can technically use the same gasket again. If you’re using the gasket again, soak it in soapy water so it makes installation easier.

Step 3: Put the Gasket on the New Window

Your new sliding window should also use a gasket for installation. If you purchased a urethane-based slider, it won’t work.

Take the new window and install the gasket on it. Be sure to do this slowly so you don’t tear the gasket at all.

You’ll want to fully seat the glass in the gasket. This is done by pressing the rubber into the glass until it stops moving. Do this all the way around the glass.

Step 4: Install the Window

The installation is a little tricky and can get frustrating. The trick that worked the best for me was to use a screwdriver to push the rubber all the way through.

Here’s how it works. Grab your window and hold it from the exterior of the truck. Press it into the frame. Use your screwdriver to take the interior half of the gasket and push it through to the interior. This leaves the exterior half on the exterior.

Continue using the screwdriver to keep pressing in the rubber all the way around the truck.

Step 5: Clean and Finish the Installation

A gasket-prepped window takes less time and effort to install. To finish the installation, just use Windex to clean the interior and exterior of the glass (making sure not to get any on your truck’s paint). Double-check to make sure the gasket is completely pushed through to the cab-side of the glass all the way around.

Give the window a few slides to make sure it works properly. Congratulations on installing a rear sliding window on your pickup truck.

You Can Also Have a Mechanic Do This Job

If, at any point of the installation, you doubt your abilities and don’t know what to do, don’t worry. Mechanics can do this job for you pretty easily, but it will cost you. Based on your location and truck, it could be a few hundred dollars.

My two cents? The project is pretty straightforward, and I think you can handle it on your own. It will save you money if you don’t mind spending a few hours on it.

Does This Work if You Have a Truck Cap?

If you installed one of those shells that turn your pickup into a makeshift SUV, you might wonder if you can still install a sliding window at the rear of your truck.

The good news is that you absolutely can.

The truck cap shouldn’t interfere with your sliding window at all. Most options on the market will sit on top of your bed with some connection points, and they don’t interfere with your window.

The key is to remove the cap before starting this process. It will get in the way and make the whole process more complicated than it needs to be.

Conclusion

I hope that you know everything you need to know about installing a new sliding window into your truck. The end result is really great, and the process isn’t super difficult. If you want to see more useful guides, explore my website. Be sure to see what great products I recommend for every car driver.