2007 Freightliner drive axles, probably meritor axles. It has Conmet Preset (internal spacer) hubs with 1 piece Axilok nuts. The Conmet site says 300 ft*lbs torque. Just want to double check, as nuts were probably 50ft*lbs on removal.
No help here other than if you pulled them off because they were leaking, you've probably determined why.