Changed the O2 sensor on the CRD, now seeing 9L per 100km (Hwy) on dash. That's with 245/75/17 A/T Wranglers! & I actually travel 104km for every 100km on the dash. That's about 1 litre better then I have ever got (using dodgy jeep trip metre
).
Heading to Philip Island in a couple of weeks, will get a better idea of fuel economy then.