well... the x5 wasn't designed as a primary tow vehicle.. otherwise it would have transmission and differential oil coolers and other heavy duty equipment dedicated to towing (alternator, more cooling out of the radiator, gearing change, etc etc etc) like a F350 Powerstroke truck...

i'm sure it does fantastic but as a long term dedicated hauler, i'm not convinced its the correct setup and longevity may be compromised... dedicated hauling does alot of punishment on the vehicle... i have yet to hear of an x5 that tows ~6000lbs always every weekend... with trips from 300 to 1000 miles one way...

are you asking oil for the x5? i used the standard 15w30 castrol or mobil 1 synthetic for the engine (i got the full oil change kit a few times from crevier - i used it in the oil change diy).... the tranny oil i bought from the dealer also.