Why do you think it is a driveline problem???
symptoms sound a lot like the usual XH/G or AU falcon fuel/electrical problems
the two all time most common later model falcon probs to check
1.ignition leads - cross firing is common problem - look for white discolouration where leads touch or are near any metal
2. fuel system (injectors/pressure modulator/etc) is it using exessive fuel??
alternatively
if it has the hydratrak diff, how long ago was the oil changed? and did they replace it with LS oil?
PS if it is dedicated gas or dual fuel - almost certain it is leads or wrong heat range plugs