Simple Question

I have what is probably a simple question for someone knowledgeable about cars. I recently changed the rotors and brake pads on my 2001 Alero. In doing so I stripped the head on a bolt that attached the Calper Mounting bracket to the hub. I replaced the damaged bolt with one purchased at a local hardware store. It was a size 12 x 1.75 silver colored bolt I bought for a dollar. I intended to replace this bolt with an identcal replacement one from the dealer, however, they wanted $10 for the bolt.

I am more than willing to spend the $10 for the bolt if it is somethig I need to do for some reason I am unaware of. Is the original bolt made of a special material and should I replace my substitute? Thanks for your help, I am inexperienced in working on cars.

The original bolt is hardened. Probably a grade 8. It is not a good idea to replace these pieces with soft hardware store bolts. Go to a junkyard. They can probably get you one for a buck or so...
Mark

Or Lowe's. They have those bins with the right hardware. Just take your old one and match up length and thread and look in the hardened bolts. SAE bolts come in regular (grade 2), grade 5, and grade 8. Anything above that is measured in psi of tensile strength. Metrics are measured in 8.9, 9.9, and 10.9 strengths and are comparable to the SAE grading system. Go with a 9.9 or 10.9 metric replacement Lowe's bolt and you should be fine and dandy.

The junkyard is a great idea, as is the parts store. Usually they have brake replacement parts like springs, bushings, and those bolts for about $2.

Thank you both for your help/suggestions. You were correct, the bolt I needed was rated 10.9. I found replacements at a local specialty hardware store for $1.00. Did not realize the bolts are labeled with their rating on the head. ($10 from GM, I thought that was a little high! If they had said $4.50, I wouldn't have thought twice, I would have just grumbled some!)

With all due respect to everyone here, it might be an error to use a hardware store bolt for this application. Graded nuts and bolts are one of the most common 'knocked-off' items around. Many millions of 'counterfiet' fasteners make their way into North America. These bolts always have high strength markings but often are substandard. I would trust fasteners from a reputable chain auto parts or hardware store, but there are many retailers that sell the fake stuff.
Be careful.

Good call, MagicRat. I've bought some from Fastenal (I think its www.fastenal.com (http://www.fastenal.com)) and they are all made in-house in the US. There are some specialty bolts that they source out, but as far as good old fashioned bolts, they are really great pieces.

Well, thanks again. I definitely do not want to take chances with my brakes. I have to admit, with GM charging $10 a bolt, I expected to pay more than a $1 for them. However, the place I purchased them from is a reputable business and has been in business for a number of years. I was referred there by NAPA.

If a Grade 8, 12 x 1.75 bolt was purchased in bulk, what would one expect to pay on a per bolt basis? At this point, I will probably use the ones I purchased, for now, and see if I can obtain an exact replacement from a junkyard.