How to Install Truck Window Run Channels

Applies to: Chevy C10, C20, K10, K20 (1960-1972, 1973-1987 Squarebody), Ford F-100, F-150, F-250, GMC Trucks, and most classic American pickups.

What Are Window Run Channels?

Window run channels (also called "glass run channels," "window felts," or "fuzzies") are the U-shaped rubber or felt-lined channels that guide your door glass as it rolls up and down. They:

Seal out wind, rain, and dust
Prevent window rattles and vibration
Allow smooth, quiet window operation

When these channels wear out, you'll notice wind noise, water leaks, and rattling glass—common complaints on classic trucks.

Rigid vs. Flexible Channels: Know the Difference

Truck window channels come in two main types, and choosing correctly is critical:

Type	Construction	Best Use	Bending
Rigid (Metal Core)	Stainless steel core with felt or rubber lining	OEM-style replacement; follows factory contours	Must be bent to shape using pliers or channel bender
Flexible (Rubber Core)	All-rubber construction, sometimes with felt lining	Universal applications; easier installation	Bends by hand; conforms naturally to curves

💡 Which Should You Choose?

For stock restorations: Rigid metal-core channels match original equipment.

For ease of installation: Flexible channels are more forgiving and easier to fit, especially on trucks with worn or slightly misaligned door frames.

What You'll Need

New window run channel kit (side and top pieces)
7-Piece Trim & Pry Tool Set (GL-30)
Nitrile Gloves (GL-10)
Phillips and flathead screwdrivers
10mm socket (for some GM trucks)
Needle-nose pliers
Weatherstrip adhesive (3M GL-11) — for securing ends
Clean rags
Masking tape

All-in-one solution: The Complete Installation Kit (GLK-1) includes everything you need for a professional installation.

Step 1: Remove the Door Panel

You must access the inside of the door to replace window run channels.

Roll the window all the way up and tape it in place with masking tape to prevent it from dropping.
Remove the window crank handle (if manual) by pushing in the retaining clip with a trim tool or using a window crank removal tool.
Remove the door lock knob by unscrewing or pulling straight up.
Remove all visible screws around the door panel perimeter (check the armrest and behind the door pull).
Use a trim tool from the GL-30 set to carefully release the door panel clips. Work around the edges—don't pry too hard or you'll break the clips.
Lift the door panel up and off the door. Set aside.
Carefully peel back the plastic vapor barrier (if present) to access the window mechanism.

Step 2: Remove the Old Run Channels

Side Channels (Vertical):

Look for screws or clips at the top and bottom of each vertical channel.
On many GM trucks (1967-1987), the channels are held by screws at the top and friction-fit into a slot at the bottom.
Remove mounting hardware and pull the channel straight up and out.

Top Channel (Horizontal):

The top channel runs along the top of the door frame, above the window glass.
It may be secured by screws, clips, or pressed into a channel in the door frame.
Remove any fasteners and slide the channel out.

⚠️ Note: On some trucks, the glass must be lowered partially to access and remove the channels. Work carefully to avoid scratching the glass.

Step 3: Clean the Channel Tracks

Remove all old rubber, felt debris, and adhesive residue from the door frame channels.
Wipe the channels clean with a rag dampened with isopropyl alcohol.
Inspect the metal tracks for rust, bends, or damage. Address any issues before installing new channels.

Step 4: Prepare the New Channels

For Rigid Metal-Core Channels:

Compare old to new: Lay the old channel next to the new one. Note any bends or curves.
Transfer bends: Use needle-nose pliers or a channel bending tool to replicate the curves from your old channel onto the new one.
Test fit: Insert the channel into the door frame track without forcing. Adjust bends as needed.

For Flexible Channels:

Measure and cut: Flexible channels often come in longer lengths. Measure the required length for each position and cut with a sharp razor blade or scissors.
Cut clean: A clean, square cut ensures the channel ends meet properly at corners.

💡 Tip: For the top horizontal channel, many trucks use a flexible channel that slides into the door frame track. No bending required—it conforms naturally.

Step 5: Install the New Run Channels

Installation Order: Install side (vertical) channels first, then the top (horizontal) channel.

Side Channels:

Insert from the top: Slide the channel down into its track in the door frame.
Align mounting holes: Match screw holes at the top with the door frame holes.
Seat the bottom: Ensure the channel bottom sits firmly in its lower slot or bracket.
Secure with screws and check that the channel is straight and seated uniformly.

Top Channel:

Slide the top channel into its track along the top of the door frame.
The ends should overlap or meet the top of the side channels.
Secure with any factory clips or screws.
Apply a small dab of 3M adhesive (GL-11) at each end where the top channel meets the side channels—this prevents the channel from shifting over time.

Step 6: Test Window Operation

Remove the masking tape holding the glass.
Carefully roll the window down and back up several times.
Listen and feel: The glass should glide smoothly without binding, scraping, or rattling.
Check the seal: With the window fully up, there should be no visible gaps between the glass edge and the run channel.

If the Window Binds or Sticks:

Check that channels are straight and not twisted.
Ensure no debris is in the tracks.
Verify the channel is the correct size (not too tight for the glass thickness).

If the Window Rattles:

The channel may be worn or undersized.
Check that all mounting screws are tight.
For flexible channels, ensure they haven't compressed or shifted out of position.

Step 7: Reassemble the Door

Reattach the plastic vapor barrier (use new adhesive tape if the original is damaged).
Position the door panel and press the clips back into place.
Reinstall all screws, the door lock knob, and window crank handle.
Test the window operation one final time.

Vehicle-Specific Notes

Chevy/GMC C10, K10 (1967-1972):

Uses felt-lined metal run channels on the sides.
Top channel is often flexible rubber.
Access requires removing the vent window assembly on many models.

Chevy/GMC Squarebody (1973-1987):

Available in both rigid and flexible configurations.
Many restorers prefer flexible channels for easier installation.
Window balance mechanism is inside the door—take care not to damage springs.

Ford F-100, F-150 (1953-1979):

Earlier models use rigid metal-core channels.
Channels may be integral with the vent window frame—replacement may require vent window removal.

Ford F-150 (1980-1996):

Transition to more flexible, all-rubber channels.
Generally easier installation than earlier models.

Troubleshooting

Problem	Cause	Solution
Window won't roll up smoothly	Channel too tight or misaligned	Check alignment; ensure correct channel size
Glass rattles when driving	Channels worn or too loose	Replace with new channels; ensure tight fit
Wind noise at highway speeds	Gap between glass and channel	Check channel seating; may need thicker channel
Water leaks into door	Channel ends not sealed	Apply adhesive at channel joints
Glass scratching	Debris in channel or damaged felt	Clean tracks; inspect felt lining

Maintenance Tips

Lubricate annually: Apply a light silicone spray to the run channels to keep window operation smooth.
Avoid petroleum-based lubricants: They can degrade rubber and felt over time.
Inspect during washes: Check for debris buildup in the channels and wipe clean.

Ready to eliminate window rattles and wind noise? Browse our complete truck window channel selection by year, make, and model.

Jan 9, 2026