MPG

[bigjim]

Wow ! a lot of good advice... I must admit I have tended not to rev the engine thinking it would save fuel so I will rev it a bit more and change and little later. I'll also try the diesel magic suggested.

Any more info would still be gratefully accepted !

Cheers

Peter

In my experiance Reving an engine is more benifical than labouring an engine, my mav is more efficent in fuel when allowed to rev hard if i labour the engine EG to low a gear and it dont repond to putting your foot down quickly its labouring (Under reving) this is inefficant let the revs produce the torque, but i dont recon 22 mpg is to bad for a big motor like yours :arrow: :roll: :lol:

 

[Sarnie109]

It really does depend on how you're driving. I'm on my second 2.7 TDi and i generally drive at around 2000 to 2500rpm and get an easy 30mpg. Driving like this on the motorway has returned a best of 34mpg and that was in a lwb Mav. Tanking along at 80 can see thinks drop to 25 ish mpg. I've a colleague who's a right old codger with a lwb and can get 36mpg and in contrast, another with the same model as him and only gets low 20's (15mpg with a caravan) but he drives it like a sports car. Hope all of this is some help.

 

[andrewk]

the physics are that a doubling of speed doesn't just double the effects of wind resistanmce, IIRC it increases exponentially (?).

The power needed to overcome air resistance is proportional to the cube of speed. A doubling from 30mph to 60mph would, therefore, require 8 times the power, just to overcome the increased air resistance.

 

[andrewk]

I recently went to Scotland with a roof box and family and I am getting about 22mpg. Is that normal ?

I've had a MkV Patrol 3.0 SVE (essentially the same engine as yours, I think) for a few weeks now and have topped up the tank a few times so that I can check fuel consumption. On the first re-fill (after having started full), over about 200 miles of mixed town and motorway (probably about a 70-30 mix), I got 23.3 mpg. On the next refill, over 300 miles, I got 27 mpg (mix 20% urban, 20% motorway and 60% A road).

On that basis, your 22mpg driving mostly motorway, dual carriageway and wide A roads (big assumption on my part) seems a bit low to me, unless you tend to drive on the limit for most of the time.

 

[smallzoo]

Thanks for that..

I think what I need to do is fill the tank up ( when I get my wages in !! ) and then try a proper MPG test. I am basing my calcs on waiting for the red light to come on.

No I dont drive on the limit, in fact I am probably being over cautious with the patrol as I am not used to it yet..

I will let you know..

Cheers

 

[andrewk]

I think what I need to do is fill the tank up ( when I get my wages in !! )

I know what you mean. Last year I paid 110 pence litre at Strontian and later again at Lochinver. Now, let's think --- 95 litres x 110p = .......

As an aside, 22mpg is about what I got from an Isuzu Trooper towing a 1500kg caravan to and around Scotland . The Trooper told fibs, though, as the odometer (and speedo) was about 8% out - so it really was no better than 20mpg.

My best guesses at the moment for the Patrol (speedo and odometer are spot on compared with my GPS) are pretty much in line with Nissan's estimates, i.e. 20 urban, 30 ish extra urban and 25 ish overall. I don't expect to better 20mpg towing - though, who knows.

Cheers
Andrew

 

[lexi]

22mpg is disappointing for a ZD30...even a fully loaded one. Do a long run unloaded and see if you can achieve the 30 mpg that a modern DID engine should give.

Running up and down the Highlands well loaded I last clocked my older engined TD42 at 24mpg. Book figures on old model was 19-29for standard manual. Mine is auto with 33s. I have a lock up switch fitted to torque convertor and drive for economy though.

Alex