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Hi Jack

My concern is fuel economy my 1997 Nissan cifero 2.5 returns. I tow a trailer with two enduro style dirt bikes and drive with and egg on the throttle never exceeding 90kph. I keep the acceleration smooth and get a return of 14.5 litres per hundred (19.5mpg.) I drive the Taupo road a lot and instead of maintaining top gear up the big hills I drop into second and sit in the torque range with a very light throttle opening. Nothing changes even when driving at a smooth fast 100kph, it doesn’t make any difference. The air filter is fresh as are the plugs and recently my knock sensor was replaced when fuel economy dropped to 18 litres per hundred. I have googled forums and believe the car isn’t that economical to start with but I’m not aware what the town/country consumption cycles should be.

My fuel costs are over $S500 each month. My dilemma is what to buy that can tow a light trailer with the bikes and give me reasonable fuel consumption. It would be a station wagon preferably so that the roof line is longer making it suitable for carrying two open sea kayaks. Most new 2 to 3 litre cars are returning around 8 lph. (35mpg)

Having read the AA information on diesel vs petrol comparisons the understanding is they basically balance out the running costs. With a budget of $20000 is that enough to get near the newer technology that is enabling direct injection and engine management systems that give good economy. The difficulty is assessing if the move is financially viable. Forking out the dollars to get a car that gives reasonable economy looks like it leaves me out of pocket when that money would pay the petrol cost for quite some time. Then there is the fact that the Cifero would be worth only approx $4 to $5000. Do I just run it into the ground so to speak? The Cifero has 210000kms on the clock and has a chain cam drive that should go a good 300000kms with out problems of replacement.

This is the dilemma and places me between a rock and a hard place.

Perhaps there is a logical way to look at this, or a formula one can apply. Jack your opinion would be valued.

Cheers Motonut.

I understand your dilemma. The amount of money you would have to invest in a replacement vehicle will buy you a lot of fuel and this fact can’t be overlooked.

An upgrade will no doubt bring other benefits however, including comfort and driving pleasure.

It sounds like a Diesel would have to be seriously considered if you do make the change and I would not be too worried about whether you can afford the new common rail technology or not.

The 'older' Diesels are OK provided you don’t buy old bangers with huge km's. A Toyota Prado with a good service history is a good place to start looking.

To be honest, you may be surprised/disappointed at the fuel consumption regardless of what you do. A couple of dirt bikes and kayaks on the roof is never going to produce fantastic consumption to be honest.

The gap you are trying to close may not be as easy as you think and your bank balance will definitely suffer if you trade up.

Definitely not an easy decision to make.

Hi.

Might I suggest that Motonut do a return trip to Taupo without towing anything. This would determine if the car was economic or not.

From my own experience, towing a trailer or even having bikes on a bike stand can significantly affect fuel consumption, even on long highway trips.

A tank of gas to and from Taupo is by far cheaper than spending $20k for a replacement.

Hope that helps.

I have a 2004 Subaru 3.0 Ltd automatic.

I have recorded fuel economy of about 9l/100km from Waiouru to Wellington with the car alone.

I recently towed a horse float half filled with household goods (so not excessively heavy) on the same route and managed only 16l/100km. I had even filled with 98 octane to help provide the engine with extra power too. Trailers really suck the fuel.

Also don't think just because you're getting a diesel truck that you'll get magical fuel economy. Look at the specs for new HiLux etc and you will see their combined consumption is still around 9 to 10l/100km. This is entirely due to the weight and energy required to work the drivetrain. Add a trailer to that and fuel consumption will still be up there.

We had a 2.4Litre Mitshi Grandis (Petrol Direct Injection) - 10l/100km normal running, 22l/100 with a Caravan. We now have a Holden Monterey (Isuzu Bighorn) 3.0l Common rail diesel. 12l/100 normal running, 17l/100 towing the same caravan. Diesels and bigger engines tend to be less affected by the extra work, but bigger engines use more when not towing. Heavy 4x4 make great tow cars, at a cost when not towing.

Compare the Mitsi at 22l/100km, and say 2000km/year towing, its an extra cost of say $500, the Holden has an extra of only $160, but uses more fuel the rest of the time. Over all our annual fuel bill is probably the same. One benefit of the lower fuel consumption is bigger range - we no longer have to plan trips around where the petrol stations are and when they are open.

We looked at other options such as a newer 2.5litre common rail that would get say 8l/100km normal and 13l/100 towing, but the interest cost on $25K (@8%=2K/year), with say $5K a year depriciation made the fuel cost insignificant.
If I was you, I would keep the car (unless there was another reason to change, say it is getting unreliable), and spend the $20K on a new trail bike or two.