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Tire Trouble

I own a 2006 Cadillac DTS. In May 2012, I purchased four Tiger Paw tires from local dealership. Dealer filled them with Nitrogen. The tires were constantly losing air (about 1/2 lb/day). I went back to the dealership many times and they refilled the tires, but I was never given an adequate explanation as to why the tires kept losing air. I then went to a local repair shop and was told tags were left on the tires. After removal of the tags, two of the four tires are better. Other two still lose approximately 1/2 lb/day. I went back to the car dealership again and now I am being told there is corrosion on the wheels and that is the reason for the air loss. (They are insisting the corrosion was not there 7 months ago when I purchased the tires). They want $250 to remove the corrosion. Is there anything else to consider concerning the continual loss of air pressure? Thank you for any insight into this problem.

Corrosion on the wheels could cause air to leak out. See if the tire place you used will give you a price to clean the wheels up.

To do the job you need to take each tire off the car, then use a machine to take the tire off the wheel, clean the edges of the wheel with a wire brush, smooth the surfaces, remount and balance the tire, finally put it back on the car. Repeat this process X 2 or X 4 depending on whether you do all 4 tires or just the 2 that are still leaking.

The dealer should have taken care of this when they installed the new tires. Likely they had one of their “rookie” service techs do the job since it is a low skill job. Leaving stickers and labels on the tire in the area of the tire bead (where the tire contacts the wheel) is a rookie mistake.

Hey Peggy36

I would agree to a certain point with UncleTurbo on this one, any imperfection on the rim can cause seal issues with your bead. I also agree with the point that the corrosion should have been spotted the first time around, sorry it does NOT just appear in 7 months it takes way longer than that unless there was damage that occured to the rim in an accident. HOWEVER you also have the right to ask your shop , preferably the one you trust more, to pull the tire off the rim and show you the corrosion they say exists. If it is noticeable then you can choose to have them do the service. You can also choose to raise a stink about how many trips you’ve had to make to repair a re-occuring problem, might get some labor $ knocked off.

Best wishes

Go back to the dealership and tell them how the problem was solved by removing the tags on two tires. Also tell them that if they didn’t know enough to remove the tags, they can’t be trusted to know if there was corrosion on the rims at the time the new tires were mounted. How can the tech be trusted to log corrosion on an inspection report if he didn’t know enough to remove the tags? If (when) the service writer can’t resolve the problem for you, ask to speak to the service manager. If the service manager can’t refurbish the rims for you at no cost, ask to speak to the general manager of the dealership. IMO, they should pay for this repair since they did such a poor job to begin with. @Peggy36, I’m sure that you will use the same discreet manner that you used here when you discuss the issue again with the dealer.

I am not buying the corrosion excuse. That happens gradually, generally one tire at a time, not suddenly on all four tires. And, frankly, that problem was common years ago, but by 2006 they’d long since solved it.

My money is on the valve stems, either incorrectly installed or the wrong stems inserted (or the stems loose or overtightened, or something like that). When tires are mounted, new valves are generally installed and the valvestems are removed to allow free flow of air into and out of the tire during the mounting process. If they didn;t know enough to remove the tags, they probably messed up the valvestem installation as well.

I am conditionally agreeing with mountainbike here as long as he meant valve CORE loose or overtightened.

He did. Nice catch. A bit technical, but a nice catch.

A few minutes with a spray bottle of soapy water will sort out if the problem is around the bead or at the valve stems.

2006 Cadillac DTS has alloy wheels. Alloys are famous for corrosion at the bead. Once you bust off the tires that are being replaced you MUST wire brush the bead vigorously to remove corrosion. For good measure some bead sealer should be applied to the bead of the new tires. If this is done you will rarely have leaks. Most discount places (and even many full service garages) will not do this unless you specifically direct them. Good luck.

This is a common problem with GM alloy wheels. And the air leak might not be at the bead. But instead thru the wheel itself because of the porousity of the wheel. Here’s GM’s recommendation if this is the case.

Inflate the tire to 40 PSI.

Place the tire/wheel into a dip tank.

With a grease pencil mark the wheel areas where air bubbles occur.

Remove the tire/wheel from the dip tank and remove the tire from the wheel.

Using the grease pencil marks as a guide, scuff the inside of the wheel with 80 grit sandpaper.

Clean scuffed areas with brake parts cleaner.

Apply a thin coat of silicone gasket sealer to the scuffed areas and allow the sealer to cure for a few hours.

Remount the tire onto the wheel.

Reinflate the tire to the proper pressure and rebalance the tire/wheel.

Tester

Porosity in aluminum is a casting defect and the wheel should be replaced. But after working in a foundry that supplied parts to GM, I am not surprised at their cheap fix recommendation, especially if it is under warrantee.