Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light Illuminated, Aluminum wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat)

Customers may comment on a tire that slowly loses air pressure over a period of days or weeks.

Abrasive elements in the environment may intrude between the tire and wheel at the bead seat. There is always some relative motion between the tire and wheel (when the vehicle is driven) and this motion may cause the abrasive particles to wear the wheel and tire materials. As the wear continues, there may additionally be intrusion at the tire / wheel interface by corrosive media from the environment. Eventually a path for air develops and a 'Slow' leak may ensue. This corrosion may appear on the inboard or outboard bead seating surface of the wheel. This corrosion will not be visible until the tire is dismounted from the wheel.

In most cases this type of air loss can be corrected by following the procedure below.

Important: DO NOT replace a wheel for slow air loss unless you have evaluated and/or tried to repair the wheel with the procedure below.

1. Remove the wheel and tire assembly for diagnosis. Refer to the Tire and Wheel Removal and Installation procedure in the Electronic Service Information (SI).
2. After a water dunk tank leak test, if you determine the source of the air leak to be around the bead seat of the wheel, dismount the tire to examine the bead seat. Shown below is a typical area of bead seat corrosion.

Typical Location of Bead Seat Corrosion





Important: Other forms of slow air leaks are possible. If the body of the tire, valve stem and wheel flange show no signs of air seepage, refer to GM Service Bulletin #05-03-10-003C for additional information on possible wheel porosity issues.

3. Bead Seat Corrosion is identified by what appears like blistering of the wheel finish, causing a rough or uneven surface that is difficult for the tire to maintain a proper seal on. Below is a close-up photo of bead seat corrosion on a chromed aluminum wheel that was sufficient to cause slow air loss.

Close-Up of Bead Seat Corrosion




4. In order to correct the wheel leak, use a clean-up (fine cut) sanding disc or biscuit to remove the corrosion and any flaking chrome or paint. You should remove the chrome or paint back far enough until you reach material that is stable and firmly bonded to the wheel. On chromed wheels, try to taper the edge of the flaking chrome as best you can in order to avoid sharp edges that may increase the chance of a leak reoccurring. The photo below shows an acceptable repaired surface.

Notice: Corrosion that extends up the lip of the wheel, where after the clean-up process it would be visible with the tire mounted, is only acceptable on the inboard flange. The inboard flange is not visible with the wheel assembly in the mounted position. If any loose coatings or corrosion extend to the visible surfaces on the FACE of the wheel, that wheel must be replaced.

Important: Remove ONLY the material required to eliminate the corrosion from the bead seating surface. DO NOT remove excessive amounts of material. ALWAYS keep the sealing surface as smooth and level as possible.

Acceptably Prepared (Cleaned-Up) Wheel Surface




5. Once the corrosion has been eliminated, you should coat the repaired area with a commercially available tire sealant such as Patch Brand Bead Sealant or equivalent. Commercially available bead sealants are black rubber-like coatings that will permanently fill and seal the resurfaced bead seat. At 21°C (70°F) ambient temperature, this sealant will set-up sufficiently for tire mounting in about 10 minutes.

Coated and Sealed Bead Seat




6. Remount the tire and install the repaired wheel and tire assembly. Refer to the Tire and Wheel Removal and Installation procedure in SI.

Patch Brand Bead Sealer is available from Myers Tires at 1-800-998-9897 or on the web at www.myerstiresupply.com. The 1 Quart size can of sealer will repair about 20 wheels.

Please submit any warranty claims for Wheel Bead Seat Repair to:

For vehicles repaired under warranty, use: