The 5 pictures in this link may be useful:
If you have an E450 LD, it probably has the drive-shaft parking brake.
Did you know it is filled with oil and needs to be checked?
Uses the same type of oil as the transmission but it is a separate reservoir.
Oil level should be level with the plug.
Use a 17MM socket on the plug.
http://www.flickr.com/photos/lwade/sets/72157627503762313/
I believe "If you have an E450 LD" translates to: "If you have an E450-based Lazy Daze motorhome."
I've also read more about the parking brake in this
Lazy Daze owners forum.