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Hello all! I'm new to SeoMoz and would like to introduce myself and say thanks for all of the great content. This is definitely the premium website I have been looking for. My question is regarding a new URL structure that will be implemented with our website redesign. We are looking to make our URL's more user and SEO friendly. We will be using 301 redirects to reroute our existing structure when the site goes live. Background
I work in a company that retails automotive tires. I would consider class (performance, off-road, highway, etc.) to be the most important category, but based on our analytics we receive much more traffic from brand terms.  This is most likely because our customers are not educated on specific tire classes and generally do head term searches or search by brand / product name. Ultimately the will have to buy from a certain class based on driving habits. Link and URL Structure
(Parameters) The model page includes links to individual tire size specific pages. We are using the model page as our primary SEO page because the only difference from the 5 - 60 tire size specific pages per model will be the tire size itself. This means that all of the remaining content will be duplicated multiple times over. All links to the tire size specific page from the model page will have a rel="nofollow" attribute attached to it. All tire size specific pages will have a rel="canonical" tag pointing back to the model page Out of the following structures, which would you consider to be the best format: 1. http://www.company.com/category/brand/model
or
2. http://www.company.com/brand/category/model
or
3. http://www.company.com/tires/category/model We will append the specific tire-size to the URL on the item specific pages. Any other options or strategies will be greatly appreciated. Thanks in advance for your help!