Downsize or keep the fuel-thirsty large car?


As fuel prices increase you may think it would make perfect sense to automatically consider downsizing to a more fuel efficient vehicle. Surely, if you could reduce your fuel bill overnight why wouldn’t you start looking at selling and trading up to a much more miserly and thrifty vehicle which is going to save you dollars at the pump.

In reality, the decision is not as easy as it seems - there are several key points that need to be taken into consideration before committing to a change in vehicle or engine size.

The first consideration is the value of your current vehicle. When fuel prices start heading skyward, the value of the bigger less economical vehicles generally track in the exact opposite direction fairly rapidly. Sure, there will always be people looking for a car to meet a specific purpose and your vehicle may tick a lot of boxes for them however, the market can quickly become swamped with such vehicles. The end result; it becomes a buyer’s market and your actual sell price may be considerably less than what you were expecting. Obviously depreciation hits hardest depending on a vehicles age but to a large extent, all used car prices are set by consumer demand.

The next step is to think about is the money that you may have poured into your existing vehicle. If it’s in good nick, has been well maintained and has had all those expensive ‘big ticket’ items - such as cam belts, cooling systems, brakes and tyres - replaced or reconditioned, then it can be money wasted if you don’t get some payback from future use of the car. Vehicles are often not worth anymore with good service histories; they simply become slightly more desirable to a prospective buyer and therefore easier to sell. And what guarantee do you have that the replacement vehicle is not going to incur similar maintenance costs? As many bill payers will testify to, fuel price increases can pale into insignificance when some maintenance and repair costs are factored in.

One of the most important ownership considerations is vehicle use. In other words it must be fit for purpose. For example, if your current vehicle is used to transport children, or often used to tow or carry reasonable loads, the question needs to be asked: just how far should you compromise in downsizing to a more fuel efficient vehicle?  Carrying out the same duties and tasks with a smaller vehicle can mean a higher work load for the engine, resulting in an increase in expected fuel consumption.

Don’t assume either that a small fuel efficient vehicle will run on the cheaper 91 octane fuel. Octane requirements depend on the engine’s compression ratio and there are plenty of mid-size cars which demand a minimum 95 octane rating to allow them to perform at the their peak. Used imports can be especially confusing in this regard, with many garages and franchise dealers taking the safe option of not recommending the cheaper 91 octane fuel. Currently the price difference between the two fuels is 7/cents per litre, so the sums must be tallied if an octane change is on the cards.

Jumping out of a petrol vehicle into a diesel can also have its snags. Often the only benefit in changing to diesel is the cost of the fuel and the better fuel consumption achieved. Road User Charges and higher up-front registration fees combined with the potential for expensive maintenance costs can make diesel ownership very expensive in comparison to petrol.

Vehicle use and driving technique should also be high on the agenda when it comes down to considering what to do about rising fuel costs. Heavy fuel consumption takes place when an engine is cold, so the big winner is the local gas station when regular short trips are taking place. If short trips can be avoided or reduced then savings can be made.

The majority of motorists can improve their fuel consumption by simply changing their driving technique.

It does take concentration but using a smooth throttle and driving at a consistent speed will produce big gains for many.  Under inflated tyres also contribute to excessive fuel consumption so there are several ways fuel costs can be reduced without having to downsize the car.

There does come a day when a car has served its useful purpose and it’s time to move it on. When owners reach that point, fuel consumption and safety should be high on the priority list when the selection process takes place.

If the current vehicle is still doing its job and is in reasonable condition however, then think twice about a change based on fuel price increases alone.

A change could be become an expensive exercise.

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