Last month my car was wearing the inside of the front right tire. A local tire service did an alignment and at the same time I swapped the right front and back tires. Now it pulled to the right. I took it back to the tire dealer today and they checked the alignment, it's OK . So for an experiment I let them swap the front tires. Now it pulls slightly to the left. It it the tires ? What happens with a tire to cause that ? They are year old X-metrics from Costco. Should I take them back ?

I'm not a pro, but if it were me, I'd take em back and try to get them to discount a new set based on how much mileage has been done on them, or see if they will give you a new set.

Make sure to take with your proof that the alignment is 100% correct so that you don't get any extra headaches when arguing with them. It wouldn't hurt to have your alignment guy write a letter stating the tires are faulty etc.

Thats my 2 cents.

Alon