SHELBY GT 350 Member
Joined: Jan 2011
Location: Central Massachusetts
Yes, the ball joints and a-arms were changed part way through the 2010 model year. (see my other post on the subject to see how I figured this out . . . the hard way, LOL . . . with pictures)
The later production had a bigger ball joint with bigger shaft and a corresponding larger hole in the spindle. The earlier builds had the same ball joints, a-arms, and spindle as the 2009 cars.
I am not positive about the date, but August 2009 does sound about right . . . so your February 2010 build should have the new a-arms with the bigger ball joint, part number should be the same as 2011+ cars. Unfortunately no your buddy's parts are not the right ones . . . you can confirm this by holding them up next to yours, you should be able to see that your ball joint is bigger.
About the GT500 a-arms -- their bushings are a little harder than the regular ones, but not much. If you are looking for much firmer bushings (like for road track use) then you really need to replace the bushings in your factory arms with the poly bushings from Energy Suspension or Prothane. But that bushing swap job is a major PITA, so if you don't really need the hard bushings, the GT500 arms are the way to go.
Just make sure you get the right ones . . .
| 2010 GT coupe | Daily Driver with some Steeda and GT500 take-off stuff for the occasional track day