2007 GT - manual trans - knocking noise ??

[psxchelly]

I originally posted this on another Mustang forum, and no one answered, so I thought I would give you guys a try...

I used to have an '04 Sonic Blue GT 40th edition... now I have a 2007 Grabber Orange GT with about 1200 miles now..

Anyhow, I was on the NJ turnpike... I was on the shoulder because I needed to get my phone. Of course if you have ever driven on the NJ turnpike, you know I had to accellerate rather quickly to merge with traffice to get back on. Going about 75-80ish I heard a knocking noise. It was loud enough to hear it over traffic with the window slightly open. I slowed down a bit then it started to go away.

I took the car back to the dealer, they kept it for a day. The shop foreman said he had it up to 100 and he didnt hear any noises. I picked my car up and to make a long story short, I decided to see if I could recreate the noise. I accelerated really fast from 4th gear and it did it again but went away. I have been trying to recreate it over the last 3 or 4 days and I have not heard it since. I had the car up to 90ish on the turnpike and no noise.

Anyone know what might have made that knocking noise? The shop foreman at the dealer insists that he never heard any noises when he test drove the car. But I have heard it on 3 different ocasions now.

thanks for any help
Michelle

[eggfarmer]

It might be a Monday or a Friday car. I have known u-joints to make such a sound.

[JustSayGo]

Just to take a guess I say it is the limited slip differential that locks in under heavy accelleration and continues making a banging knocking noise until it becomes less locked. Seems odd that a new car would not have LSD additive that is used to prevent the noise.