Had to do a bit of a dash today with work,ending up doing 196 miles of motorway driving.As it was an emergency breakdown i had to drive faster than I usally do. I didnt drop below 60 apart from 20 miles of compulsory 50 mph,most of the time is about 70 or slightly above
Shes a 1996 diesel auto. Thankfully id filled her up the night before so she was full to the brim. Filled up after the job was done at the same pump and managed to pump in 30.03 liters .
Just worked it out and its about 29 mpg (sorry old school)
Im chuffed to bits!!!!¬!
Shes got a rover ron box fitted and ive put that marvellouss lucas oil additive in the gbox as well.
Looks like the thermosat being reinstalled a new rad and the removal of the viscous fan and use of the aircon fans as coolers has done the trick.
Many thanks to all those who helped me get this far, you all know who you are and Im so grateful.THANK YOU ALL
As an aside what do others get mpg so to speak?
Oh btw 29 is about 2 mpg more than my 03 dieseel td5 defender does but i used to drive her about 50 to 55 on the motorway and obviously i wasnt towing with either of them

29 mpg sounds about right to me. I am getting 15 mpg going to & from work, but on a run I get 27mpg. Somebody on here, probably Datatek or Wammers said that diesel has an anti waxing additive in the winter which reduces the mpg slightly.

Sounds ok im getting 19mpg average
But I do 15 motorway miles and 8 in heavy traffic everyday
But on a run she can get into the 30s easy
Although im a cheep scate and will tuck in behind a wagon (you'd be surprised how much fuel you can save like that )

About the same as I get on a motorway run. I get 24mpg as a long term average which drops to about 20mpg in traffic choked Worthing.

I average 17 to 18 mpg in town and get 29 to 31mpg on a longer run!!!!

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