How old are your tires

[tparker]

If your tires are cracking (inside or out), then I don't think you are using them appropriately. You need to let the smoke out a lot more frequently, then you won't have this problem

[JH27N0B]

Speaking of cracks, I've had this problem several times with the tires on my DD Dart.  The outer sidewall looked fine but the inner sidewall was cracked badly.  I didn't have records of mileage when I'd installed these tires, but an educated guess is 4 years/40,000 miles.  I put over 15,000 miles a year on the car until Covid, and since then I average 8-10,000 miles a year. These were mounted on the front.  I'd previously found cracked inner sidewalls on this cars tires while doing a rear brake job a year or two previously. Pretty scary since my commute includes highway driving at speeds exceeding 70 mph.

[blown motor]

You have an alignment problem. It makes me wonder if the extra stress on the inner sidewalls of the tire is contributing to the cracking.

[cuda hunter]

You have an alignment problem. It makes me wonder if the extra stress on the inner sidewalls of the tire is contributing to the cracking.

My thoughts exactly. 
Still though, that is quite the checking going on! 

[cuda hunter]

okay, maybe you guys are right.  I stand corrected.

Just want you to be safe.  And possibly not destroy the vehicle secondarily.

[pschlosser]

Just want you to be safe.

[YellowThumper]

This may be true, but tires do not generally degrade and oxidize from the inside.  Even a well worn, gray and aged tire, looks pretty darn good on the inside when removed.

To the contrary, my tire guy has shown me several times tires that are perfect on the outside but when you take them off and bend the tire and look inside there are little fish scale degradation spots everywhere.  I didn't believe it so he showed me multiple tires that are still in 7 year time frame that were degrading. 
  If the chinese would just use more Oil in the tires none of this would be a problem. 
  This is driven by profit.  Companies don't make money from selling you and I products that will last years and years.  That is why china has now taken the business and manufacturing away from Americans.  They make crap that will break and then we buy more. Over and over and over again. 
  Until we as a people in this country all realize this and take manufacturing back we will be subject to having all short term temporary items while we live. 

  If we could take manufacturing back and not have to buy the same thing every 2 or 3 years over and over again the money and time spent on that goes into new innovations for our people.  The money goes into the retirements of the elderly and inheritance for the family.   All of that is gone when we give it to china (and other countries) . 

Exactly true.
"Saving the planet" can come directly from extending the lifespan of every product made.
Simple things like Wiper blades used to last for multiple seasons.
Now they degrade even when stored as spares.