The Precision Glass Run Channel (GRB 6121 84) is a direct-fit replacement for the rear door vertical post that guides and seals the window glass. Designed to restore smooth window operation, reduce wind noise and prevent water intrusion, this channel fits left or right hand rear door posts on applicable vehicles—verify fitment with the GRB 6121 84 part number for compatibility. Made for durability and long-term weather resistance, it helps maintain proper glass alignment and protects interior trim from moisture and vibration.
Features:
- Durable EPDM rubber extrusion with integrated stiffening insert for reliable sealing and shape retention.
- Fits left or right rear door vertical posts; check part number GRB 6121 84 for vehicle compatibility.
- Guides and cushions window glass to restore smooth operation and correct alignment.
- Prevents water intrusion and reduces wind noise for a quieter, drier cabin.
- Direct replacement for worn or damaged channels; ideal for restoration and maintenance projects.
- Easy to install with common hand tools; resists UV and temperature degradation for long service life.
Installation / Application:
- Difficulty: 3/5
- Estimated time: 45-90 minutes
Instructions:
- Prepare vehicle: disconnect the battery if required by vehicle procedures and roll the window to the midpoint as needed.
- Remove the door panel: use a trim tool to remove clips and screws, then carefully detach the panel and set aside. Peel back any vapor barrier or moisture barrier to access the vertical post.
- Lower or raise the glass to access the top/bottom of the old channel, and support the glass (tape in place if needed).
- Remove the old channel: loosen or remove any retaining clips, then pull the old rubber channel off the vertical post. If bonded or brittle, carefully cut sections away with a utility knife and remove debris.
- Clean the vertical post: remove old adhesive, dirt, and corrosion; wipe with a clean rag so the new channel seats properly.
- Test-fit the new channel (GRB 6121 84): align it to the vertical post and slide it into position from the top or bottom as vehicle design permits. Ensure the channel lip faces the glass.
- Seat and secure: press the channel fully into place; reinstall any retaining clips or fasteners and confirm the channel is fully engaged along the post.
- Lubricate the glass run: apply rubber lubricant or soapy water to the channel contact area to ease glass movement and prevent pinching.
- Reassemble the door: lower/raise the glass to confirm smooth operation and correct alignment, then replace the vapor barrier and reattach the door panel and trim.
- Final check: operate the window several times to ensure smooth travel, listen for unusual noises, and inspect for proper sealing and water tightness.
About Precision Replacement Parts
Since 1986 Precision Replacement Parts has been a trusted name in the Automotive Glass Industry.
Our knowledge and experience in manufacturing millions of extruded and molded EPDM Rubber, PVC and HDPE based plastics, and various stamped and extruded metal products for the classic and late model industries has allowed Precision to expand our services into multiple product markets.
Along with our own USA based production facility, Precision also partners with 25 different manufactures worldwide with a reputation as a global leader supplying OEM and replacement products to a number of different industries. Our partnerships along with our own in-house manufacturing and fabrication capability gives Precision a unique position in helping to meet the expanding needs of customers everywhere, providing them with a sustained competitive advantage.
Vehicle Fitment:
The Vehicle Fitment Guide is to be used as a general reference. The data has been provided by our suppliers and manufacturers and may contain errors or incorrect data. Always refer to a professional to verify correct fitment for your vehicle.
| Make |
Model |
Years |
| Jeep |
Cherokee |
1984 - 1996 |
| Jeep |
Wagoneer |
1984 - 1990 |
