Thread: fuel usage and litre/100km

My best fuel economy is found in rolling hills. The acceleration at high load but low rpm up the hills is the engines best operating point. Coasting down the other side uses almost no fuel.

It's the same as the pulse and glide used to save fuel, but the hills make you do it.

It is easy to get apparent variations in fuel consumption unless you can be 100% sure that you filled up to exactly the same level each time.

A small slope on the ground, a fuel that froths a bit more than usual or thinking that just because froth is spilling on the ground that the tank is full can make a big difference.

Refilling the tank when it still has a significant amount of fuel still in it makes the error even greater.

I suspect the Disco filler neck is not as bad as the cab/chassis Defender, but I will offer some figures from my own experience.

If my tank was about half full and needed 30 litres to fill it and I had covered 300km from the last fill. That would mean I had used 10 litres/100km.

I know from experience that I can usually fit in an extra 5 litres after froth has reached the top of the filler neck and it appears to be full. If I wasn't careful, I would think it was full after adding just 25 litres. That would make me think I had used only 8.3 litres/100km.

It could be as simple as that or it could be that you had a gale force tailwind.

Originally Posted by vnx205

It is easy to get apparent variations in fuel consumption unless you can be 100% sure that you filled up to exactly the same level each time.

A small slope on the ground, a fuel that froths a bit more than usual or thinking that just because froth is spilling on the ground that the tank is full can make a big difference.

Refilling the tank when it still has a significant amount of fuel still in it makes the error even greater.

I suspect the Disco filler neck is not as bad as the cab/chassis Defender, but I will offer some figures from my own experience.

If my tank was about half full and needed 30 litres to fill it and I had covered 300km from the last fill. That would mean I had used 10 litres/100km.

I know from experience that I can usually fit in an extra 5 litres after froth has reached the top of the filler neck and it appears to be full. If I wasn't careful, I would think it was full after adding just 25 litres. That would make me think I had used only 8.3 litres/100km.

It could be as simple as that or it could be that you had a gale force tailwind.

Yes I do totally agree there is allot of room for variation but to change from 9 litre to 7 litre I thought was to great of a difference be from an error of different filling up levels.
I figured it has more to do with all the coasting down hill though I thought the extra revs and power required to get up hills and over some pretty rough terrain

Oh wait. This was your "offroad" fuel consumption?

In that case yes it's just the dozen different irregularities of each fillup screwing with you. A 3 tank average is the only real way to know your fuel consumption.

Fitted a Hyclone ?

Iv had my tdi auto for a few years now. It runs 31inch tyres, has a roof rack bull bar, couple of aerials

Hwy between 8 and 10 km per ltr

Hwy with camper trailer 7 to 9 km per ltr

Bush tracks forrestry trail 7 to 12 km per ltr, about the same with the trailer

Sand dunes and Sandy coastal tracks 6 to 8 km per ltr with camper 5.5 to 7 km per ltr.

These are worst and best. I took the time to work this out for trip planning. And to put it simply with a Jerry can or two the d1's reasonable size tank there's not many places you can't get to. Top little truck

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Hi 3lud13,


I'm not surprised that you returned poorer fuel economy last night after 4wding.


You will always use more fuel in low/medium speed off road work.


It takes a hell of a lot more energy to get a stationary or even slow moving 4wd to accelerate once momentum has been lost. The vary nature of 4wding demands constant changes in velocity. The acceleration required may not always be massive but the energy required to accelerate always be higher than that of commuting on the black top.


Congrats to you on taking an interest in your fuel economy though. I regularly drive off road and am amazed at how many people fail to make it out of the bush not because of break downs or anything unfortunate but because they underestimated their fuel usage!


Stumpy

Originally Posted by Stumpy1

Hi 3lud13,

I'm not surprised that you returned poorer fuel economy last night after 4wding.

Stumpy

Hmm - he got better fuel consumption not worse - 9l/100km to 7l/100km which is an improvement.