I have read different arguments around the web concerning domain names and trademark infringement. I notice that there are so many unofficial forums with the companies brand name in the domain. Some examples of xenforo forums: priuschat.com, browncafe.com (yes brown is registered to UPS). Hondatech.com is another example. There are hundreds. All of these sites have registered trademark names in their domain. They simply put a disclaimer somewhere saying they aren't offiliated with the trademarked company.
When creating a domain for a forum - do you hesitate to use the brands trademarked name in the title? xbrandsforum.com? It seems the best option for SEO, but could it be a lawsuit in the future?
I think it depends on how you use it, if it is for financial gain then you are on sticky turf, or even if it brings the company name into disrepute then again I think you are thin ice.
I don't think it will have much of an effect on your SEO either, Fords main site is surely going to outrank any other containing the word "Ford"