Driving 2001 e53 X5 3.0 without Belly pan

[squidzilla]

My mechanic is changing my differential and transfer case fluids (he has a lift) and thinks I might have a leak from the rear main seal.

Anyhow, he left the belly pan off for the drive to his house so he could check for leaks overnight. His plan is to reinstall it on Monday or Tuesday.

Is the belly pan structural at all or just a protective covering? I found a thread somewhat related to this question but is for the 4.8 which is much heavier than my car with much stiffer suspension so I did not think that was an exact comparison to my lowly 3.0.

Thanks.