I've read that the general rule is not more than 3 repairs on a tire so long as they're spaced a certain distance apart

I'm going to have discount plug/patch a second spot on one of my rears. And I tow a 6000# cargo trailer several times a year.

Does the 3 patch max also apply when towing? Or should I bite the bullet and get new tires? I've got probably 25K left so this will be painful to replace 12-15 months early.

I should add the first flat resulted in my driving 300yards to the nearest parking lot to put on my spare. It was completely flat so I've wondered about the sidewall integrity.

These are SL tires not E rated

Thank you

I echo what Silvy said. If you had destroyed the sidewall running the tire flat for too long, they would've told you. Sorry for bad luck but you're likely fine.

I can't believe you got Discount repair it a second time. They always have some reason they can't repair any tire I bring them and I end up having to do it myself.