Here's a nice interview I stumbled across with Googlers from the Google Search Quality Team. They were asked to share their experiences and knowledge about Google, what impacts search ranking and a few tips on what you shouldn't be doing! (The article claims to interview ex-Googlers, but I'm not so sure about that claim.) Regardless, this is still helpful info for anyone involved with ensuring their website runs as effective a possible.
1. Quality content is more important than fresh content
Fresh content can have a positive influence on the rankings of a web page as long as the content is high quality content. The quality of your web pages is more important than their freshness.
Why quality? Quality gets shared and when content is shared it creates social signals - think popularity signals - and additional links and activity around your site.
2. Internal link anchor texts are important
Internal linking with optimized anchor text makes it easier to understand your website navigation. For that reason, you should use meaningful anchor texts on your web pages.
This is such a common mistake made within dealer websites - pages will link to each other using anchor text such as "click here" - "hours" - "for more information." Make this anchor text relevant to the page you're linking to: "Vehicle trade in calculator" is much better.
3. Overusing AdSense and other ad systems can hurt your rankings
Although it is okay to display ads on your website, overloading a website with ads can influence your website’s visibility in Google’s search results. This is not limited to any particular ad system.
While most dealers don't place ads on their primary website (not sure why you would) - however many dealers do try this on their landing pages and blogs. Just be smart about the amount and frequency. If your goal is affiliate marketing and ad revenue, then you need to consider the branding emphasis being placed on those sights so you don't hurt your overall efforts.
4. Linking to other websites is important
Some people think that not linking to other websites is a good practice. The ex-Googlers recommend to link out to sources you trust. Linking to pages that are relevant to the content of your website is normal. If you’re unsure about the quality of a page, just use the rel=nofollow attribute. “Ask yourself, would you trust a scientific report without any citations to other scientific sources? Most likely not.”
In the past I would link to industry reports, Green Car white paper reports and Government mileage/MPG reports. This is a great opportunity to create helpful content and link to it other pages using relevant long tail anchor text. (Which they confirmed was important in item #2 above)
5. Being a Google AdWords customer does not help your organic rankings
According to these guys Google AdWords and organic search are completely separated from each other. Changing your Google AdWords budget won’t have any effect on the algorithmic evaluation of your website.