drumroll...

[Heysüß]

sound coming from the back of the car. (sounds like someone is doing a drumroll with wrenches)

If i drive in a normal manner the sound goes away, but if I try to do any type of spirited driving it happens in 1st and 2nd gear. It seems like there is not enough torque to cause the drumming sound to happen on the rest of the gears. Do you guys think the entire final drive needs to be replaced?

the sound is RPM dependent so it gets faster and slower as the RPMs modulate in 1st and 2nd.

[nando]

bad flex disk/guibo and/or CSB and/or u-joints

start with the flex disk

[jlevie]

I agree. Unless the guibo is obviously bad and falling apart, the fault will be in the CSB & drive shaft.

[bmwm42]

Fix it asap just make sure you make a line on the ds when you replace the csb to keep it balanced

[Heysüß]

I guess I should respond with what was broken since I hate it when others don't.

The rear subframe was completely broken at one of the bolts at the top of the differential where it attaches to the frame. So when the m30 torque from 1st and 2nd came in, the diff vibrated so bad that that's what was making the drumroll sound (the broken section tapping away like a marching snare drum)