rattling noise?? (rear end)

[Axel Grungy]

i have a 91 s13 fastback, when im in first or second and let off the gas, i hear this rattling noise from the rear end. it sounds like i have rocks rolling around in my trunk. it only seems to do this when the car is cold. could it be axels? driveshaft?? i have searched but found nothing....someone please shed some light.

[ss240]

have the same thing on my car

keep the car running and go back and see if the exhaust is loose (wiggle it left to right)

if it make the same sound you will just have to rebolt it down or secure it in some way