How to Tell if You Have Run-Flat Tires

Tuesday, February 14, 2012 by Ben Rooney

Many new cars are equipped with run-flat tires. These tires give the ability to keep driving on a tire that has lost air. Typically, self-supporting tires maintain vehicle mobility for 50 miles at speeds up to 55 mph. The exact ratings will vary by tire and vehicle. 


Car dealers often fail to mention to customers that their tires are run-flats or may mistakenly indicate that a car has run-flat tires when it does not. To find out whether your car has run-flat tires, check the sidewall. 


The International Organization for Standardization (ISO) has developed a universal symbol for self-supporting run-flat tires, represented by a flat tire continuing down the road: 

Run Flat Tires - Tech Article

In addition, tire manufacturers have special branding to indicate run-flat capability. The following is a list of the branding used by manufacturers we carry:  

See an example of a tire with run-flat branding here (Dunlop SP Sport 600 DSST CTT - Original Equipment the Nissan GT-R). The DSST CTT branding is near the 12 o'clock position on these Dunlop car tires. The ISO pictogram is immediately to the right.

Comments on How to Tell if You Have Run-Flat Tires

Wednesday, November 6, 2013 by Karen Mcfall:
Bought used Mini Cooper. Trying to find out if it has run flats. Definity HP800, treadware 400, traction A, temperature A, radial tubeless, made in Korea, 195/55R16 87H, Dot 5MNY EK B... can you help?
Wednesday, November 6, 2013 by ben@tirerack:
Hi Karen. We do not carry that brand, so we could not say for sure. I would recommend to check for the ISO symbol mentioned in the post above. It should be present on any runflat tire.
Sunday, November 10, 2013 by Jesse:
I just purchased a car with Bridgestone Potenza tires. I couldn't find neither the ISO symbol nor the RFT branding on it to confirm it is run flat. I found the branding RSC imprinted on the sidewall. Is it the same as RFT? Tire is a 245/40R19
Thursday, October 9, 2014 by john russo:
275/35/zr/18/99y ... dealer says these are run flat... i say no...
Wednesday, December 17, 2014 by boshomane sp:
im driving bmw 320d i want 205/55/r16 run flat tyre make kuhmo xrf can i get some

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