Overview
Van cargo doors—commonly called "barn doors"—present unique installation challenges because they consist of two doors that meet in the center. Proper seal orientation is critical to prevent water intrusion and ensure both doors close correctly. This guide covers both side cargo doors and rear cargo doors on full-size vans.
Understanding Cargo Door Seal Components
Cargo door weatherstripping typically includes:
| Component | Location | Notes |
|---|---|---|
| Door-Mounted Seals (Left & Right) | Perimeter of each cargo door | Compress against body when closed |
| Body-Mounted Seal | Around the cargo door opening on the van body | Door closes against this seal |
| Center Pillar Seal | Where the two doors meet | Prevents water/air intrusion at the centerline |
| Lower Threshold Seal | Bottom of door opening | Critical for water protection |
Note: Rear cargo doors on full-size vans are sold as a pair (driver side and passenger side). They are NOT interchangeable.
Identifying Left vs. Right Door Seals
Metro Moulded Parts uses a color dot system to help you identify seal orientation:
| Dot Color | Side |
|---|---|
| 🔴 Red Dot | Driver Side (Left) |
| 🟢 Green Dot | Passenger Side (Right) |
Tip: If your seals aren't marked, dry-fit each seal before applying adhesive. The molded corners and contours will only fit one way.
Tools & Materials Needed
- 3M Black Weatherstrip Adhesive (GL-11)
- 7-Piece Trim & Pry Tool Set (GL-30)
- Nitrile Gloves (GL-10)
- Denatured alcohol or adhesive remover
- Clean lint-free rags
- Masking tape
Save Time & Money: The Complete Installation Kit (GLK-1) contains all the adhesives and tools you need.
Step 1: Remove Old Seals
- Open both cargo doors and secure them in the open position.
- Identify the mounting method:
- Push-on seals: Grip a metal flange. Peel back and pull steadily.
- Adhesive-backed: Use a plastic pry tool to separate without damaging paint.
- Clip-retained: Release clips before removal.
- Remove ALL old adhesive from both the doors and the body opening. Use adhesive remover and a plastic scraper.
⚠️ Warning: Residual adhesive is the #1 cause of seal failure. Take your time with surface prep.
Step 2: Inspect and Prepare Surfaces
Before installing new seals:
- Check for rust on the door edges and body opening. Treat with rust converter if necessary.
- Clean all surfaces with denatured alcohol and allow to dry completely.
- Verify door alignment. Misaligned doors will not seal properly regardless of new weatherstripping.
- Check door hinges and latches for wear that may prevent proper door closure.
Step 3: Install Body-Mounted Seal First
If your application includes a body-mounted seal (around the cargo door opening), install it first:
- Dry-fit the seal around the entire opening without adhesive.
- Starting at the top center, position the seal and work outward and down both sides.
- Once positioned correctly, apply adhesive in sections:
- Apply a thin bead of 3M Black Weatherstrip Adhesive (GL-11) to 12-inch sections
- Press seal firmly into place
- Continue around the perimeter
- Pay special attention to corners—apply extra adhesive at corner joints.
Step 4: Install Door-Mounted Seals
Determining Correct Orientation
Cargo door seals are designed to seal in a specific direction:
- The bulb (rounded portion) of the seal faces outward—it compresses against the body when the door closes.
- The flat mounting surface attaches to the door edge.
Critical: If the seal is installed backward, the door will not seal properly and may be difficult to close.
Installation Order for Rear Barn Doors
Always install the PASSENGER SIDE (right) door seal first, then the driver side. This matches the door closing order—driver side door overlaps and closes last.
- Identify the correct seal using the color dot system (Green = Passenger/Right).
- Dry-fit the seal on the passenger side door perimeter.
- Starting at the top hinge corner, work around the door:
- Top edge → Latch edge → Bottom edge → Hinge edge
- Apply adhesive in sections and press seal firmly into place.
- Repeat for the driver side door (Red dot = Driver/Left).
Step 5: Install Center Pillar Seal (If Applicable)
The center pillar seal prevents water intrusion where the two doors overlap:
- Position the seal on the overlapping door (usually the driver side door on rear barn doors).
- The seal should run the full height of the door edge.
- Use adhesive along the entire length—this seal experiences significant stress when doors are opened/closed.
Step 6: Install Lower Threshold Seal
The threshold seal at the bottom of the cargo opening is critical:
- Clean the threshold channel thoroughly—dirt and debris collect here.
- Insert the seal into the channel, working from one end to the other.
- Apply adhesive at both ends to prevent the seal from migrating.
- If your seal is adhesive-backed, ensure full contact along the entire length.
Step 7: Close Doors and Verify Seal
Check the passenger side door first:
- Close slowly and observe seal compression.
- The seal should compress evenly around the entire perimeter.
- There should be no visible gaps.
Then close the driver side door:
- Ensure it overlaps correctly with the center pillar seal.
- Both doors should latch without excessive force.
- Check the center seam for any gaps.
What to Expect: The Break-In Period
⚠️ Important: New Metro SUPERsoft rubber seals are manufactured larger than compressed originals to ensure a positive seal.
Doors may feel stiff for 1-2 weeks. This is normal and expected.
- DO NOT adjust door strikers to compensate for tight doors.
- Close doors firmly during the break-in period.
- The rubber will conform and compress over time.
- Applying heat with a heat gun (on low setting) can accelerate break-in.
Troubleshooting Cargo Door Seals
| Problem | Likely Cause | Solution |
|---|---|---|
| Doors won't close easily | Normal break-in period | Allow 1-2 weeks; use heat to accelerate |
| Water leaking at center seam | Center pillar seal missing or damaged | Install/replace center pillar seal |
| Water at bottom corners | Threshold seal not seated properly | Remove and reinstall with adhesive |
| Wind noise at highway speeds | Seal not compressing evenly | Check door alignment and hinge wear |
| One door harder to close than other | Seal orientation incorrect | Verify Left/Right orientation (Red/Green dots) |
| Seal pulling away | Adhesive failure or dirty surface | Remove, clean thoroughly, reinstall |
Special Notes for Side Cargo Doors
Side cargo doors (Dutch doors) on vans like the Chevy/GMC G-Series follow similar principles:
- Upper and lower sections may have separate seals.
- Install the lower door seal first if doors overlap.
- The hinge-side vertical seal is critical—ensure it runs the full height.
- Some applications use a channel-type seal that slides into a metal track rather than adhering to the surface.
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)