Arrgg! (about bad wheel mounting job)

[napapacoda]

I just purchased some 16" wheels for my 1998 civic. I decided to go to costco to have my tires mounted there since I've gone there before and normally they are pretty good. This time it was anything but. First the guy was a bitch saying that he won't mount aftermarket wheel/tire packages after making me wait 2 hours in line. Luckily the manager was in and he did it. He did the first 3 wheels and then vanished when a new worker came in. This asshole put the wheel on, but must not have done something right with the valve stem because im driving 2 days later and just by chance my music stops so i can actually hear stuff outside and hear this weird noise coming from my tires, im like FU_K!!!. So i pull over and see that the tire is basically flat, it looks like it has air in teh top, but on the bottom its just running on the squished side wall. so I pull over and change the tire, but I dont know how long ive been riding on it like that, it was at least .5 miles if it happened over night or more if i just didnt notice it. It wasnt like a normal flat though because I had a flat in my other car and you can feel vibrations, this time it drove normally.

First, do you think that the tire is any good now that ive driven on the side wall like that?? I refilled the tire with air last night, but did not look at it yet. What I can tell is that if you push the valve stem down a little bit you can hear the air coming out, so thats at least one problem.
Secondly if the tire is no good now, do you think that I can prove it was costco's fault and they should pay for a new tire? Any good arguing advice(I will be seeing them tonight about this)? Lastly, how do you tell if the tire is ruined or not?

[LordKoo]

Bring it back and bitch... speak to the manager, make a big hooha... I am sure things will work out for you!

[napapacoda]

thanks for the reply. I talked to the guy and he said it was due to a bad valve stem seal (lol like i didnt know that when i brought it to him). He unmounted the tire from the wheel and inspected it, he seemed honest and told me that the tire had no damage and that it will be fine to drive on. The problem was that my wheels came with high pressure valve stems and they only carried ugly bronze looking high pressure valve stems so they didnt put on new ones. But they forgot to check the bolts to make sure the valve stem was on tight. So now I have to check my other 3 tires to make sure the other valve stems arent loose. But he sounded like if there was damage he would have replaced the tire for free. i bet he could get away with pro-rating it if by "accident" a nail went in it.