We’ve seen 4x4s take a hammering this year.

Used values have been falling faster than other sectors and earlier this month we found evidence that the larger petrol models are being refused as part exchanges.

We know road tax for these cars is expected to reach more than £400 a year by 2010 while fuel costs will have increased by about 20% compared with 12 months or so ago.

Although owners of these six and eight-cylinder cars are suffering, we appreciate dealers who specialise in them are also finding life tough.

A recent search of the classified ads found a few pre-registered models that were £10,000 and more off the official list price.

We found Hemi-powered Jeep Grand Cherokee models on 08-plates – pre-facelift as supply of petrol to the UK models dried up last year – at less than £23,000. This is about £14,000 off the official list price.

The high performance SRT-8 model – arguably a pointless addition to the range as it is neither a sports car nor an off-road vehicle – has been seen in the classifieds with between £10,000 and £15,000 off list price.

And it isn’t just the mainstream brands that are suffering.

We’ve found examples of the Lexus RX350 LE limited edition at main dealers at below £26,000.

Depending on specification, these cars retail from just under £35,000 to £38,000.

It’s possible to find BMW X3s being sold under the company’s Used Approved scheme, but with a few hundred miles on the clock at £10k or so below list price.

If this is what’s happening to cars that are ‘new’ in all but name, the impact on used values will be devastating.

While the market is currently volatile, it will surely settle down again in the future, but by then used values for these petrol models will be significantly lower than they had been until recently.