Scalloping is Not Just for Potatoes; It’s for Tires, Too

Dear Bree,

Riddle me this: What do you call it when your tire has a funky-looking, scalloped pattern on it?  While I almost admire the decorative look to my tires (it’s even symmetrical!), I know it’s only there because something is wrong.  I think even wear on the middle of the tire or on the sides is about inflation, but what is this all about?  Am I going to have to buy new tires?

Clueless in Clearwater

Dear Clueless,

You’ve described the pattern very well as being “scalloped,” but we also call this particular wear pattern “cupping.”  There are a couple of things that can cause cupping, and a few things you should look for to try to determine the cause.

First, where is the cupping located on the tire?  Down the middle, inner or outer edge?  The location of the wear is important in diagnosing the problem.

Second, how does the car (or truck) drive?  Is there a lot of vibration, especially as you increase speed?

Cupping happens when a vehicle is bouncing and the tires get scuffed every time they come down; if you’re bouncing, eventually, cupping happens.  The problem you have to solve first is the bouncing.  If your tires are cupping, it’s probably because you have a suspension problem.  Maybe your shocks are worn out or you’re having a problem with wheel bearings or bushings, or a bent control arm.  If the scallops are down the center and large and broad, it’s probably your shock absorbers.  Underinflation can cause lots of small scallops, but if the scallops are deeper, sharper and less tapered, then you’re probably looking at unbalanced wheels or bad wheel bearings.

If the scalloping on your tires is happening along the edge, it could be indicative of a problem located more deeply in your suspension system, so get ready to brush out some cobwebs and really get in there.  Cupping on the edges could mean bad wheel bearings, but it may also mean bad ball joints, bad steering or sway-bar end links, problems with the steering linkage or control arm, and/or really messed up bushings.  This usually happens when the wheel is compressed during cornering from some element in the suspension vibrating or bouncing.  This is not a problem you want to let slide or put off. At RNR TIRE EXPRESS, we offer free tire inspections, so stop by any RNR and they can steer you in the right direction.

The other reason you may see cupping: You’ve got low-quality tires.  Would these happen to be the tires that your car came with?  Sometimes the tires your car comes equipped with at buying time aren’t the best tires you can get, so if you need to replace them, do some research, come in and talk to us at RNR for more info, and buy a good-quality tire that will really last for you.  The money you spend up front will be well worth it in the future, and at RNR you’ve always got options: easy payment plans, 120 days same as cash, and instant buyer rebates on all cash purchases.

As far as actually needing new tires, I can’t tell you because I haven’t seen the damage.  It’s possible you could rotate the tires after fixing the problem, but recognize that the less rubber actually meets the road, the less traction you have and consider your safest option.  We know finances are always a consideration, but paying the price of unsafe tires can have consequences that go way beyond your wallet

My advice: See a mechanic, have the problem diagnosed and fixed, and let us take a look at the scalloping and give you our best advice.  If you need new tires, we can help you find a payment plan that works for you, and if you’re safe with a rotation, we can take care of that too.

Good luck, Clueless, and be safe!


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