D40 Fuel Usage

[holby80]

G'day,

I bought a 2010 Navara D40 recently and am pretty disappointed in how much fuel it uses. It's a diesel, dual cab, auto and has canopy, roo bar, roof racks, rear wheel carrier and 31" tyres which I know will be hurting the economy but the fuel usage still seems a bit excessive.

Currently its using around 15L per 100kms, or 6.5kms per litre which seems a bit excessive.

Any ideas of what could be going on, or is this usual for this model.

Cheers

 

[happy john]

Hello holby, have a read here mate.
Cheers
http://www.navara.asia/showthread.php?t=39

 

[david m]

Hi,have a 2013 V6 diesal, showing an average of 10.4 litres per 100k.
dual battery, draws and 265/65/17 tires, canopy and TJM side steps. Cheers

 

[Old.Tony]

15LPHK is a little high even for mixed highway/city use. I've found that I use more fuel the faster I go, but even using the freeways at 110km/h my consumption is averaging out around 12.7-12.9LPHK.

Does your car blow excessive black smoke? How's the car's performance? If it's really sluggish there might be an issue with the turbocharger (more likely the control mechanism, not the turbocharger itself). There might be excessive dust on the MAFS (yes, it does get dirty). You might have a split hose in the vac system - there's a number of things that could cause the issue (not going to mention sticking brakes because you would have already felt the hubs to see if they're warm, right?).

 

[Czechmate]

I use mine for work so fully loaded with roof racks loaded with ladders

Ive got an 07 STX auto with dpf, 265 75 16 mud terrain toyos
Aggressive my ud terrains make a BIG difference to fuel use

Souped up clutch fan so it runs almost all the time

All these things contribute to high fuel use

I get around 16-17 litres per 100k in steep hilly windy terrain, the local area

Was amazed once when i had it unloaded with roof racks off, all the gear out and 70 profile all terrains on, i got 10 litres per 100ks, as it should be

I think if your nav is loaded up and you wanna move quickly, shes gonna suck some juice

Good thing about the d40 STX is they have the power and suspension to do so

 

[holby80]

Cheers for the replys,

The vehicle seems to be performing normally - plenty of power and doesn't blow any smoke. It does around 2000rpm at 100km/hr so the motor isn't working excessively. I mainly do highway/country kms which is why I thought I might get a bit better economy.

I bought with all the accessories already on it so have never run it in stock form. Luckily it has a long range tank so at least I can almost a 1000kms before filling up!

 

[Old.Tony]

Part of the problem with 100km/h or more is that you're asking a big box to push its way through the air at those speeds.

A perfect example: a bicycle. You've ridden one. I've ridden one. I cruise at about 25km/h on my mountain bike, I can pedal it up over 30km/h (maybe mid 30s) but that's all. It's not a racing bike. At around 50km/h, aerodynamics start to overwhelm the average cyclist. You have to be extraordinary like this guy to go faster.

Or you improve the aerodynamics like this guy.

We can't really do much to our cars, so the trick is not to adjust it, but to NOT push the car as hard. We use considerably less fuel at 90km/h compared to 100km/h.

Try a tank of fuel at 90km/h peak.

 

[happy john]

I'll use an example, I'm near 2.8tonne now and run 32's. Cruising I'll get around 10.5lph. Just got back from a weekend in the scrub and had to be home in a hurry. Sitting on 130 it drank 16lph.

 

[Czechmate]

Haha yea d40s are not the most aerodynamic of vehicles

Its amazing the huge difference to fuel use fitting aggressive mud terrain tyres makes too

Jacked up my use by more than a litre per hundred ks

 

[fitzie]

Hi guys im having aproblem with fuel usage but also blowing black smoke, i have replaced maf sensor, vac hoses and turbo control solenoid. Any ideas why still having problem I would gladly appreciate.

 

[Old.Tony]

I'd say it's still starving for air. Any boost figures available? How long since the intercooler's been out and had a clean with petrol?

 

[fitzie]

I haven't done for while. I have never cleaned the intercooler is there anything I need to know before I do it

 

[fitzie]

I meant I haven't done boost figures in awhile

 

[Old.Tony]

Cleaning the intercooler is easy. Steps with a pic of the little beastie can be found here.

 

[fitzie]

Thanks Tony I'll give the intercooler a clean and see how it goes after that