Thread: 3.9 V8 Fuel economy!?

Sell it and buy a diesel.

You won't get a lot better than that around town.

You should check the vacuum advance unit and the air flow meter.

500km for 100litres when measured correctly is 20l/100km which is really at the worse end of fuel consumption around town - my standard 3.9 would give 14 on the highway, 17-18 around town. Now you have all this extra gear so 20 might be about right - noting similar products from Nissan and Toyota give about the same fuel consumption.

I would get a full tuneup - plugs etc and see what happens but you fuel consumption is not all that bad but petrol V8 pulling over 2 tonnes is never going to be good - I guess you bought the wrong vehicle.

Garry

Driving a barn door at any speed will suck the juice. Leave the roof rack home on weekdays! Buy a Corolla for commuting and live the dream on the rare occasions you actually need a lifted truck. Or perhaps look at a gas conversion...

If you dont want diesel go gas. For an injection system should cost about $2-$2.5K after govt rebate(maybe a bit more if you go triple tanks in load area on floor) and same economy/power, for the old system will be about $1k-$1800 but less power and 15-25% worse economy. So if you save $50 per tank or $100 per thousand K's you will have paid for it in 25,000 k's.

Sounds about right for a 3.9. My recently departed Soft dash classic ran 20-22l/100km around town, 17-18 l/100km towing a trailer on the highway and 25l/100km towing a 1.8 tonne caravan.

You are probably where it's at, I have a Disco2, V8 and have kept a log on fuel/ travel over 6 years and 190,000 kms. I keep the vehicle in first class condition and my usage in the burbs is approximate to 5.5km/litre/91 Octane (LC engine) this would provide a range of 522 kms/95l tank.
On the highway Adelaide/Melbourne I get around 7 kms/litre (660km range), some fuel brands perform better than others, higher Octane premium fuel or ethanol blends at 94 octane make no difference.
However driving style can make a dramatic difference, I did tests for comparative analysis and if you heavy foot them you pay. With my vehicle the ideal sweet spot when on the highway is about 2300 revs,in the burbs I think the biggest loss is idling at the lights and constant stop start.

I prefer not to know . . .

But I live in a small town and take months to go through one tank.

I think Fitzroy Crossing does qualify as a small town. But it has a BIG and cheap for the area petrol station and a GREAT caravan park/camping ground/ hotel/restaurant.

I am sure they have rebuilt the Supermarket by now since the unfortunate fire a couple of years ago.

Regards Philip A