Rear end noise

[Ryan Singh]

So for the past week, I've been getting this noise coming and going only when the car is cold. Today and yesterday is the first that it happened two days in a row.

When I start it in the morning, it sounds fine while I'm parked. I can rev and still it sounds fine. As soon as I start moving, I hear a sound that sounds just like what it would sound like if I were to drag an empty pop can. I stop, and it goes away. Once the car is hot, it stops completely...also it sounds as if it's coming from the rear end somewhere. I'm thinking that it's the differential...low on fluid maybe?

What do you guys think? If it's the diff, how hard is it to change the fluid?

Thanks,
Ryan

[John Hartman]

fluid change is easy.  Jack it up, put a pan under the diff, pull the plug(22mm socket), pull the fill plug(same socket) and let it drain out.  When its done, put the drain plug back in and then fill it up with some Redline 75/90 shockproof gear oil(Lordco, on the shelf).

I would also look at your rear brake, to see if something is stuck in them or bent.  Look at your axles, driveshaft etc.  Could be a foreign object(no not a dude from merry ole England) stuck in between the driveshaft and the exhaust, or could be a bent heat shield on the exhaust touching the driveshaft.

This might also be something totally different.