I was going to install new wheel locks today and I noticed that one tire had hairline cracks on the area that meets the lip of my rims. It goes around most of the tire. Anyone know if these are just cosmetic cracks or if I should replace these? I've never had cracks there before and only one tire has this issue. Build date of the tire is week 41 (October?) 2015.

 

Was the tire chronically under inflated and therefore more flexing at the sidewalls?

The tires are three years old. I think the industry standard is to replace at 5 year mark even if plenty of treads left.

Personally, I would just go ahead and replace ALL four tires with brand new tires. I don't mess around on the tires.

Last year on my SLK55 AMG HARDTOP CONVERTIBLE I discovered all four tires had cracks along where the treads meet the sidewalls on outter perimeters of the tire sidewalls. The tires were like two years old and plenty of treads left. I had only put on like 5 thousand miles!!! But the car was not driven much bc I drove the RCF instead! I had to replace all 4 tires.

 

They were never under-inflated. Were your cracks similar to mine or larger?

 

Mine were way more serious and visible. But on the more "outter perimeters" of the tire side walls all the way around where the treads meet the side wall. Mine was all season Michillin PS (3? or 4?, I don't remember) tires. My tires were properly inflated too. It was due to ''dry rot" bc I did not drive that MB SLK55 AMG HARDTOP CONVERTIBLE that often after I got the RCF!!!

Depending on how old/mileage on yours......you maybe able to file a claim with the tire company or the store (Lexus dealer if bought new) sold them to you?

 

Tire cracking is usually an age issue. I've had friends tell me too much tire shine over time or inflation issues can cause it.

In my personal opinion, I do think small hairline cracks are fine since the outside of the tire is only really there to protect the structural integrity of the inside. If the cracks get worse/deeper I would replace them ASAP just for peace of mind.

 

https://info.kaltire.com/is-tire-cra...-related-wear/