Just taxed Mrs B's 2013/63 Berlingo 1.6/115PS HDi for £130.

A lot less then I pay for my 2005/05 1.9D/68PS version.

The whole VED system is in terrible trouble.

Please explain.

Looks to work OK to me.

Because revenues are collapsing. When they introduced the cheap road tax bands they never imagined that so many car manufacturers would make cars in these bands and so many people would buy them.

Therefore, year on year, as car costing nearly £300 to tax are replaced on the road with ones costing £30 or less total tax take drops and the drop is going to significantly accerate.

There is currently a review going on regarding road tax and you can except all the goal posts to be moved again in terms of which cars are cheap to tax.

The obvious target for vehicle tax increases will be diesel cars - due to the higher levels of nitrogen dioxide they produce.

Older ones, yes - Euro 6 diesel NOx limit has been slashed to not much more than petrol.

The issue with diesel emissions seems not to be so much when they are new, but that they now appear to get much worse than predicted as they get older. Who knows if euro 6 will be any different.

That applies to any car, diesel or petrol, if its not been serviced regularly or correctly. The highest mileage I have ever done in a car was 113,000 from new in a Golf. After the first service I did all the maintenance (to the VW schedule using VW parts and lubricants) myself and never had a problem at the MOT. A few weeks before I sold the car I was stopped at a roadside emmisions check, the operator was amazed they were so low on a car with that number of miles.

Another factor with diesels is owners who fit these tuning boxes that alledgedly produce lots of power and better economy but in reality all they appear to do is produce huge amounts of smoke when the owners boot the car.

And don't forget the DPF. Of the 6 diesels we have owned 4 have smoke when accelerated fast and 2 have not. Those 2 have been fitted with DPF's. Take off the DPF and I can 100% guarantee they would smoke.

At least DPF removal is hopefully a thing of the past if MOT garages do their jobs correctly.

All the current emissions are a bit of a con. In reality, cars are not really much "cleaner" or more economical than those of 10 or 15 years ago.

All that has happened is that more advanced engine managment has made it easier for them to do well in the very simple EU test.

Where I think VED is a bit silly is that you have Mr & Mrs Retired doing 2500 miles a year in their £800 Mondeo 1.8 which does 35mpg and costs nearly £300 to tax.

You then have a £35k BMW 520d driven by Mr Salesperson for 20,000 a year which costs £30 or less.

That isn't really fair as it is quite clear who "pollutes" the most.

It's made fair by the amount of fuel duty paid - none of us can escape that.

It isn't even an insurance check anymore so, apart from being a non-progressive tax which costs a lot to adminster, what is the point of it?

Seems reasonable enough for tax on vehicles to combine both fixed element (VED) and progressive (Fuel Duty). VED shouldn't cost a lot to administer as vehicle is registered and easily detected if being used on road.

I suspect though that we will see fixed element moved away from being related to emmissions as mfrs have 'gamed' result and a fixed charge of say £100-200 pa would be fairer.