D40 Fuel Economy

[Old.Tony]

I did a search on some Triton figures and what I've seen are marginally better than the Navara's but nothing outstanding. Similar around town, and marginally better on highway towing.

Some of the posts claim to have directly compared the Triton and Navara and find the Navara a LOT thirstier but didn't provide figures.

I could similarly say that my Navara is a LOT faster than Mark Webber's race car but without producing how the measurement was taken (Mark's car parked in pit lane, my car rolling down a hill) you'd all want to take a spin in my car to see what it was like.

 

[nonno]

I picked up my D40 STX-550 a week before Christmas, (traded my 06 D40 STX auto). We brought our 20.5ft caravan home from Orbost to Benalla via the Great Alpine Road. I think this is the harder of drive, given you're travelling uphill all the way till you get to Mt Hotham. I got 11.8l/100km towing the van. Without the van I'm getting 9.2km/100litres. I'm wrapped - and oh the power. In my view if you're going to buy an STX you wouldn't even consider the 2.5L 4 cylinder anymore as the fuel savings over 5 years would more than cover the additional capital cost of the vehicle.

 

[joe2006]

OT,

Maybe it's one of those "The grass is always greener..." things?

Wifie hangs $%it on me nowdays because I drive for economy (trying to keep under 2000rpm). Near impossible without a tailwind & on level ground when towing though.

This sounds interesting: http://www.automatictransmission.com.au/release.asp?NewsId=41246.

I see they have a torque converter manual lock up kit for some models as well but it appears not for the Navara.

A chip is another cosideration but there is so much mud throwing by the various companies that it is difficult to know which ones are best. In any event I will have to wait untill it's out of warranty & it may very well be retired from towing duties by then.

P.S can anyone cofirm whether the stall speed is really 3000rpm?

 

[Old.Tony]

That's part of the fun of the internet, Joe. You have to decide who's pissing into the wind, and who's looking over the fence at someone else's garden.

Someone pointed us at that company before and it's a very intriguing idea to be able to lock the converter manually. It means you could flick the switch and plant your foot, which will open up the fuel rail pressure some more, but not as much as if the gearbox kicked down - so you don't consume as much fuel.

The manual states 2700-3100rpm with the gearbox oil between 50C and 80C.

I don't think it's worth trading up to a 550 for me. I'm using (on average) about 6LPHK more than nonno (welcome to the forum, mate!), but I can do without the heat issues that it's apparently having - including ballooning of the charge air hoses.

 

[KraftyPg]

Maybe it's one of those "The grass is always greener..." things?

If the grass wasn't greener people wouldn't upgrade you have to take into account that models currently on the market should get better economy than previous models. There would be no point if manufacturers released the new model and couldn't get the economy figures down as well. Even the 12kw upgrade to the D40 a few years ago got better figures than the previous model with basically the same bits under it.

 

[Arty_74]

30-40% more fuel, yeah right! Based on that figure an 09 manual the same as mine would have to get 240-320ks more out of a tank of fuel than mine. I haven't heard of too many Nav's without LRT's that get over 1000ks per tank.

3-4% maybe (although not going by my figures) but 30-40 someones writing fanciful articles.

10 LPHK plus 30% = 13 LPHK ! (this is what many of us are getting)

What is wrong with APC's statement?

 

[KraftyPg]

For one it's not what I'm getting but for two adding 30% because of a DPF is ludicrous it's doesn't use that much more fuel. If my DPF was using 30% of my fuel I'd be challenging Honda drivers for economy.

 

[Old.Tony]

Our return trip saw us use 12.1LPHK (remember it was 10.6 on the way down. That's a 14.3% increase in fuel consumption and I know the exact reason for it.

Both trips were done with the cruise control on most of the time.

The trip down, I'd held the vehicle at around 95-97km/h in 100 and 110km/h zones. On the return, I took it up to the speed limit.

It proved to me quite clearly that going too far beyond the 2,000rpm mark comes with a penalty in fuel usage.

 

[joe2006]

Our return trip saw us use 12.1LPHK (remember it was 10.6 on the way down. That's a 14.3% increase in fuel consumption and I know the exact reason for it.

Both trips were done with the cruise control on most of the time.

The trip down, I'd held the vehicle at around 95-97km/h in 100 and 110km/h zones. On the return, I took it up to the speed limit.

It proved to me quite clearly that going too far beyond the 2,000rpm mark comes with a penalty in fuel usage.

That's why I have been thinking bigger tyres might help but of course as they say with every action comes an equal & opposite reaction.

Keeping the rpm below 2000 also puts me in the pissed off truck driver zone. Too slow for them to sit behind but quite hard to pass on a single carriageway.

That's when wifie looks at the passing truck, looks at me, shakes her head & tries to sleep as a sign of disgust.

Thanks for the info on the stall speed. Crikes it is high.

Some of the Challenger lads that have installed the AT lock up kit & valve body upgrade were impressed with the outcome. I can post the link but probably of no relevance seeing as the AT lock up kit is not available for the Navara. I think I can recall reading of Patrol owners doing the same?

Now if I knew how to multiquote.....

Although there was a period when emission laws became dramatically more stringent & succeeding model vehicles actually produced less power while consuming more fuel. Inevitably they overcame this hurdle & vehicles have generally become increasingly more efficient while at the same time becoming bigger & heavier in order to stroke our egos & accommodate our increasingly large arses. So yeah I agree with your comments Krafty. Not that you had mentioned the bit about large arses & egos because that would likely end up down the path of D40 vs D22 and I would like to think we are all much too precious for the for that sort of nonsense.

Hey does anyone remember the fuel crisis and the Commodore 4? The VC Commodore with the mighty Starfire 4 engine? That one knocked the world on it's arse. Ooh la la.

 

[Old.Tony]

That's why I have been thinking bigger tyres might help but of course as they say with every action comes an equal & opposite reaction.

Unfortunately I am using more fuel - something like 1 litre per hundred km - my 265/70R16 tyres are 2% larger than the standard 255/70R16s.

Keeping the rpm below 2000 also puts me in the pissed off truck driver zone. Too slow for them to sit behind but quite hard to pass on a single carriageway.

That's when wifie looks at the passing truck, looks at me, shakes her head & tries to sleep as a sign of disgust.

My attitude is that the posted speed sign indicates a speed LIMIT, rather than a speed TARGET. If I am not impeding traffic in any way, then everyone else can go around.

Thanks for the info on the stall speed. Crikes it is high.

Some of the Challenger lads that have installed the AT lock up kit & valve body upgrade were impressed with the outcome. I can post the link but probably of no relevance seeing as the AT lock up kit is not available for the Navara. I think I can recall reading of Patrol owners doing the same?

I thought they had released something to do it. I suppose once the warranty is out - if I am annoyed with the 'box - I'll give them a call.

As it stands, I'm not terribly upset with it. It's smooth, the TCC locks up under the appropriate conditions and unlocks if the stress is a little too high. That's not an entirely bad thing.

Now if I knew how to multiquote.....

Copy everything inside the square brackets with the "QUOTE=" including the numbers and paste this BEFORE what you're quoting. Paste in the stuff you're quoting. End it with the /QUOTE enclosed in the square brackets.

 

[joe2006]

Unfortunately I am using more fuel - something like 1 litre per hundred km - my 265/70R16 tyres are 2% larger than the standard 255/70R16s.

No doubt OT you have done all the relevant calculations relating to changes in the odometer reading and you are using something like 9% more fuel, less 2% for the increased tyre size, therefore a net increase in the region of 7%? Presumably the only other factor which may be responsible for a very small portion of that increase would be tread pattern if you had changed to something a little more aggressive.

I thought they had released something to do it. I suppose once the warranty is out - if I am annoyed with the 'box - I'll give them a call.

As it stands, I'm not terribly upset with it. It's smooth, the TCC locks up under the appropriate conditions and unlocks if the stress is a little too high. That's not an entirely bad thing.

Yeah in all honesty I would hate to be dropping the box unless it was broken.
Something much less invasive & easily reversed perhaps?

Copy everything inside the square brackets with the "QUOTE=" including the numbers and paste this BEFORE what you're quoting. Paste in the stuff you're quoting. End it with the /QUOTE enclosed in the square brackets.

If the grass wasn't greener people wouldn't upgrade you have to take into account that models currently on the market should get better economy than previous models. There would be no point if manufacturers released the new model and couldn't get the economy figures down as well. Even the 12kw upgrade to the D40 a few years ago got better figures than the previous model with basically the same bits under it.

Quoted for no other reason than to demonstrate I can now multiquote but as to whether I can remember your instructions.......

 

[KraftyPg]

Quoted for no other reason than to demonstrate I can now multiquote but as to whether I can remember your instructions.......

And here I was thinking you actually found something meaningful in one of my posts. You'd be a first but I was excited for a second there.

 

[Old.Tony]

No doubt OT you have done all the relevant calculations relating to changes in the odometer reading and you are using something like 9% more fuel, less 2% for the increased tyre size, therefore a net increase in the region of 7%? Presumably the only other factor which may be responsible for a very small portion of that increase would be tread pattern if you had changed to something a little more aggressive.

I just add 2% to the odo reading that I take every time I fill up. I've posted the formula that I use somewhere here, but basically it just multiplies the distance value by 1.02 and that should be close enough.

Yeah in all honesty I would hate to be dropping the box unless it was broken.
Something much less invasive & easily reversed perhaps?

I was looking through the manual to determine whether or not it would be possible to activate the TCC on my own by wiring something into place myself.

The TCM is not easy to deal with. It has an external interface that allows it to communicate through the CAN to the ECU but basically the TCM controls the internal components itself and bases its decisions on the info from the ECU (throttle position, vehicle speed and such) and the sensors within the gearbox.

Basically it means that there's no real way to trigger the TCC unless you tap into the computer that's located in the bottom of the gearbox.

It's not something I'd want to do unless the 'box had a problem either.

 

[joe2006]

And here I was thinking you actually found something meaningful in one of my posts. You'd be a first but I was excited for a second there.

No I did agree with it earlier, it's just that I couldn't multiquote then & it was covered my verbal excrement.

 

[KraftyPg]

No I did agree with it earlier, it's just that I couldn't multiquote then & it was covered my verbal excrement.

No I did agree with it earlier, it's just that I couldn't multiquote then & it was covered my verbal excrement.

No I did agree with it earlier, it's just that I couldn't multiquote then & it was covered my verbal excrement.

I can do it too

 

[d22dave]

Does that mean he,s talking shite lol

 

[KraftyPg]

If he's quoting me he is in part.

 

[navdog_d40]

ok mine got to 700 then the light came on thats not even highway im happy with it

 

[Bplastered]

500k's per tank. around town or on a trip. Cooper LTZ 285 50 20's and a DP chip.
Shameful!

 

[KraftyPg]

That is pretty bad, I hope DP chip manufacturers don't claim fuel economy improvements with those kind of figures. Although I am sure there is more to it than just the chip.