It's fixed! The 5th gear vibration I've had (see
http://www.allfordmustangs.com/forum...coupe-5th.html) has finally been repaired! After replacing the drive shaft and rear end assembly, turns out it was something faulty in the transmission. Took it out for a test drive during lunch, and it's smooth as silk. I'm SO relieved! Now I can continue planning my mods.......!
On the downside, the car now has a "jiggle". When I go over bumps, and randomly cruising, there's a "ba-dumpa-dumpa" coming from somewhere on the front-ish passenger side. It sounds like maybe a cable or something light weight, possibly plastic. I'm guessing maybe a wire/cable wasn't placed back in its hanger correctly, or something like that. I also noticed a 4" plasticky tag thing attached on one of the hoses down around the
tranny, so that may be the culprit. I'll tinker with it once I get it back and see what's causing it... it doesn't sound like anything major.
Again, I'm SO glad they were able to finally find the problem! Parkway Ford in Adairsville, GA is AWESOME!
~HA
2008 Mustang GT... Hallelujah! No more drivetrain vibration! 
