Not sure if this needs to go in tire section....

• Found two nails on drive-rear tire today. Took it back to local discount tire where I bought the original tire 6k miles ago. Also purchased tire protection so tire was being replaced for free but I was told, I would have to pay for another tire protection ($33/tire) as original one was only good for the lifetime of original tire. Is this normal?
• Unfortunately, they didn't have the same tire(Continental DWS 245/40/19) in stock but wanted to put 245/35/19 temporarily until replacement arrives. I asked them not to thinking AWD wouldn't work mis-match. Is this true?

 

Your first point is absolutely true. That's what I HATE MOST about Discount Tire. It's a nickle and dime scheme if you ask me. When you buy your tires, you pay a fee for lifetime balance and rotation and flat repair etc and you can also purchase tire protection so you get a new tire if you hit something and the tire is unpairable. However, these lifetime services ONLY applies to the original tires you bought. Of course, they don't emphasize that when they try to sell it to you. I ran into this when I bought new tires, and within a few months, had a bulge in the sidewall of one of the tires. It was covered under warranty and the tire protection, so I get a free new tire, BUT I had to pay for install and balance again and I had to pay for a new TPMS rebuild kit as well. With taxes and all, ended up having to pay almost $50 and it was UNDER WARRANTY!

As for your second point, I haven't done the calculations, but as long as your overall tire+wheel diameter is not too different, it probably won't affect the AWD system. But this one, I'm not 100% sure about...