Tires: What tire to buy for Focus, tire debris, 2 different things

Question
QUESTION: Barry I am driving myself crazy (probably over thinking) on making a decision on what tires to buy for my wife’s focus (2007 2.0L not sporty).  This car is her daily driver with many turns to and from work.  Also she drives 460 miles all freeway every other weekend to where I'm currently working.  Now we are dealing with Arizona heat and a speed limit of 75mph witch means she drives 80mph.  I can’t even begin to count all the blow outs I've seen on the side of the freeway and even horrible accidents. I need a tire where I can have a good piece of mind and feel confident with her driving 80MPH on these hot roads. I understand how tires are rated but there are so many!

Thanks,

Matt
Phoenix AZ

ANSWER: Matt,

What you need are tires that are at least H rated for speed.  Studies show that tire with cap plies are almost immune to separations.  With a very few exceptions, H rated tires will have at least one cap ply.

But let me distinguish between 2 different things - separations and run flats.

Separations are the loss of structural integrity between the components of the tire.  Typically these are caused by underinflation, and aggravated by speed and ambient temperature.  When you see tire debris along the side of the road that is just a piece of the tread - that's a separation.

Run Flat is a condition where the tire loses its ability to hold air - typically because there is a puncture.  The failure mode is that the tire will split into 3 pieces - the tread (in the shape of a hoop) and the 2 sidewalls.  

Tires with cap plies are relatively immune to separations, but are just as susceptible to punctures as lower speed rated.

That should cut down on the number of tires for you to compare.

---------- FOLLOW-UP ----------

QUESTION: Is there a better tire than others that hold up to the AZ heat?

Answer
Matt,

Like I said, H speed rated and higher are practically immune to the problems associated with heat.  It doesn't matter which brand you get.

But I should tell you I work for a major manufacturer of tires and feel it is unethical for me to comment on a specific brand of tires.  If you sort through all my answers, you'll never find a brand specific comment.