2021-2026 Jeep Wrangler / Gladiator Door Hem Corrosion

Owners of 2021-2026 Jeep Wrangler and Gladiator vehicles may notice a specific type of degradation on their vehicle doors. This issue, identified as "Filiform corrosion at the hem area of the door," is a form of corrosion that can affect the aluminum body panels. Technical Service Bulletin (TSB) 31-001-26, issued on February 17, 2026, provides a detailed repair procedure for this condition.

This TSB is applicable to Jeep Wrangler (JL) models from 2018-2026 and Jeep Gladiator (JT) models from 2020-2026, specifically for vehicles sold in North America, Enlarged Europe, China, Middle East & Africa, and South America markets. The primary cause of this problem is identified simply as corrosion.

Symptoms

The main symptom customers may experience is "Filiform corrosion at the hem area of the door." This type of corrosion appears as thread-like filaments growing under the paint film, often originating from a scratch or break in the coating. If you observe this on your vehicle's door hems, it indicates the presence of this specific corrosion issue.

Diagnosis and Trigger Conditions

Diagnosis for this issue is straightforward. If a customer reports or a technician observes the symptom of "Filiform corrosion at the hem area of the door," the repair procedure outlined in TSB 31-001-26 should be performed. There are no specific fault codes (DTCs) associated with this body panel corrosion.

Repair Procedure Summary

The repair for the Jeep Wrangler door corrosion involves a multi-step process to remove the existing corrosion and refinish the affected area. The procedure, detailed in TSB 31-001-26, includes:

1. Door Removal and Preparation: The affected door is removed and placed on a padded stand to protect its exterior surface. The trim panel and carrier plate are also removed.
2. Corrosion Removal: Factory-applied seam sealer is removed, and any pitted areas are cleaned using a 3M Clean & Strip disc or equivalent abrasive wheel.
3. Sanding and Cleaning: The existing OEM coating is feathered-edged beyond the bare aluminum areas using 320-400 grit sandpaper. The area is then cleaned with PPG SX533 Aluminum Cleaner, followed by PPG SX503 Aluminum Conditioner.
4. Masking and Priming: The inside of the door is masked using a reverse taping technique to prevent paint build-up. One to two coats of F4921 Epoxy Primer are applied, with care taken to melt in the edges of the primer.
5. Seam Sealer Application: 2K seam sealer is applied in the hinge opening areas and along the exposed hem seam. Special attention is given to reducing the width and feathering the seam sealer near blend areas.
6. Refinishing: After ensuring no pits or sanding marks are visible (applying primer surfacer if needed), basecoat color is applied to achieve color match and hiding. This is followed by a clearcoat application.
7. Final Protection: Masking tape is applied to drain holes to prevent overspray. Finally, 3M Cavity Wax or an equivalent product is applied to the inside of the door shell between the door skin and frame for additional protection against future Jeep Wrangler door corrosion.

Required Tools or Parts

To perform the repair for this Jeep Wrangler door corrosion, specific materials are required:

• 3M Clean & Strip Disc
• PPG SX533 Aluminum Cleaner
• PPG SX503 Aluminum Conditioner
• F4921 Epoxy Primer
• 3M Cavity Wax

These parts are listed as NPN (No Part Number specified), indicating they are generic or commonly available workshop supplies.

Important Warnings

Owners and technicians should be aware of specific instructions provided in the TSB:

• CAUTION! Allow one-hour dry time or force dry for 25 minutes at 60 °C (140 °F) for the epoxy primer to dry before applying seam sealer.
• NOTE: For SA (South America) market only, after applying this TSB, it is not necessary to send DID-I or DID-A (Dealer Information Document - Inspection or Dealer Information Document - Authorization).
• NOTE: If pits or sanding/grinding marks are noticeable, apply primer surfacer (not shown) to achieve filling.
• NOTE: Allow clearcoat to air dry overnight or force dry for 25 minutes at 60 °C (140 °F).

Owner Action

If you observe "Filiform corrosion at the hem area of the door" on your 2021-2026 Jeep Wrangler or Gladiator, it is recommended to schedule an appointment with an authorized Jeep service center. The repair, identified by Labor Operation Numbers 23-75-53-07 (front doors) and 23-75-54-07 (rear doors), has an estimated labor time of 3.9 hours per door. The failure code associated with this repair is ZZ. A material allowance of $46.46 is also noted. This repair is reimbursable within the provisions of the vehicle's warranty.

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Source: NHTSA ID: 11029684