Overview
Sliding door seals on full-size vans (Chevy Express, GMC Savana, Ford Econoline, Chevy/GMC G-Series) consist of multiple weatherstrip components that work together to keep water, dust, and wind noise out. This guide covers the proper installation of both door-mounted and body-mounted sliding door seals.
Understanding Your Sliding Door Seal Components
Full-size vans typically use a two-seal system for sliding doors:
| Seal Type | Location | Function |
|---|---|---|
| Door-Mounted Seal | Attaches to the perimeter of the sliding door itself | Primary seal that compresses against the body opening |
| Body-Mounted Seal | Attaches to the van body around the door opening | Secondary seal that the door closes against |
| Lower Threshold Seal | Bottom of the door opening (on body) | Prevents water intrusion at the step area |
Important: Some applications require both door-mounted AND body-mounted seals. Check your order to ensure you have all necessary components before starting.
Tools & Materials Needed
- 3M Black Weatherstrip Adhesive (GL-11) — For securing seals in critical areas
- 7-Piece Trim & Pry Tool Set (GL-30) — For safe clip and seal removal
- Nitrile Gloves (GL-10) — Keep adhesive off your hands
- Clean rags and denatured alcohol or adhesive remover
- Masking tape (to temporarily hold seal in position)
Pro Tip: The Complete Installation Kit (GLK-1) includes adhesive, gloves, and essential tools—everything you need in one package.
Step 1: Remove the Old Seal
- Open the sliding door fully and secure it in the open position.
- Identify how the old seal is attached:
- Push-on style: Grips a metal flange. Peel back one corner and pull steadily along the length.
- Adhesive-backed: Use a plastic trim tool to pry gently without scratching paint.
- Clip-retained: Locate clips and release them before pulling the seal.
- Remove all old adhesive residue using adhesive remover or denatured alcohol. The surface must be completely clean and dry.
⚠️ Warning: Do not skip surface preparation. New seals will not adhere properly to dirty or oily surfaces.
Step 2: Inspect the Mounting Surface
Before installing the new seal:
- Check for rust or corrosion on the metal flange or body opening. Treat any rust with a rust converter before proceeding.
- Verify all mounting clips (if applicable) are present and functional. Replace any broken clips.
- Ensure the door track and rollers operate smoothly. A misaligned door will prevent proper seal compression.
Step 3: Dry-Fit the New Seal
Never apply adhesive until you've test-fit the seal.
- Starting at the top corner of the door opening, position the seal and work your way around the perimeter.
- For door-mounted seals, begin at the top rear corner of the door and work forward, then down.
- Check that:
- The seal sits flush against the mounting surface
- Corners align properly without bunching
- The seal lip faces the correct direction (toward the body opening)
Step 4: Install the Seal
For Push-On (Friction Fit) Seals:
- Start at the top corner and firmly press the seal onto the metal flange.
- Work in small sections (6-8 inches at a time), ensuring the seal fully seats onto the flange.
- Use a plastic trim tool to press stubborn sections into place.
For Adhesive-Backed Seals:
- Peel back approximately 6 inches of the adhesive backing.
- Align the seal at your starting point and press firmly.
- Continue peeling and pressing in sections, smoothing as you go.
For Clip-Retained Seals:
- Align clips with their corresponding holes in the body or door.
- Press each clip firmly until it snaps into place.
- Apply small dots of 3M Black Weatherstrip Adhesive (GL-11) between clips to prevent gapping and flutter at highway speeds.
⚠️ Critical: Even if your seal has clips, use adhesive between clips. This prevents the seal from lifting away from the body and causing wind noise or water leaks.
Step 5: Installing the Lower Threshold Seal
The lower (threshold) seal is often overlooked but critical for water protection:
- Clean the threshold channel thoroughly—debris collects here.
- Slide the seal into the channel from one end.
- Apply a thin bead of adhesive at both ends to prevent the seal from creeping out of position.
Step 6: Close the Door and Check Alignment
- Slowly close the sliding door and observe how the seal compresses.
- Check for:
- Even compression around the entire perimeter
- No gaps or areas where the seal doesn't contact the body
- Smooth door operation without binding
What to Expect: The Break-In Period
⚠️ Important: New Metro SUPERsoft seals are intentionally manufactured slightly larger than crushed originals. This ensures a proper seal once the rubber conforms to your door.
Expect the door to feel stiff for the first 1-2 weeks. This is normal.
- Close the door firmly during the break-in period.
- Do NOT adjust the door striker to compensate for a tight seal.
- The rubber will compress and "memorize" the door shape over time.
- Using a heat gun on low settings can accelerate the break-in process.
Troubleshooting
| Problem | Likely Cause | Solution |
|---|---|---|
| Door won't close fully | Seal needs break-in time | Wait 1-2 weeks of regular use; apply heat if needed |
| Water leaking at corners | Corner not fully sealed | Apply adhesive at corner joints |
| Wind noise at highway speeds | Seal not making full contact | Check door alignment; add adhesive between clips |
| Seal pulls away from body | Insufficient adhesive | Remove, clean, and reinstall with proper adhesive |
Applicable Vehicles
This guide applies to:
- Chevrolet Express (1996-present)
- GMC Savana (1996-present)
- Chevrolet/GMC G-Series Vans (G10, G20, G30 – 1971-1996)
- Ford Econoline (E-150, E-250, E-350 – 1975-2014)
- Chevrolet Astro / GMC Safari (1985-2005)