Owner-drivers who sleep in the cab might put Night Lock option at top of their shopping list. By Tim Blakemore

Ask the average driver of a Daf XF about the age of its cab design and chances are that he or she will be blissfully unaware that it dates back more than 30 years.

The 95-series Daf range was unveiled in 1987, with an all-new cab to replace that of the successful 2800/3600 series.

Daf had formed a joint venture called Cabtec with Enasa, a Spanish state-owned truck-making group, long-since defunct, of which Seddon Atkinson was a subsidiary, to design and build its new and much-needed long-haul truck cab.

It is surely a powerful testament to the skill and foresight of the Cabtec engineers, all retired long ago, that their design lives on in the XF. The structure of today’s XF cab is fundamentally the same as that of a 1987 95-series.

Remarkably, the XF cab at least holds its own in most driver opinion polls by comparison with far more modern rivals.

The reason can be summed up in one word: space.

The boxy XF cab has bags of it. But Daf’s current engineers also deserve credit for having repeatedly updated the XF with features that have strong appeal for drivers and operators alike.

An XF 450 FT I drove on a short route close to the Daf Trucks’ test track near Eindhoven last month illustrates the point vividly.

It is a two-axle tractor, designed for the five-axle, 40-tonnes-gcw artic operation that is more popular in continental Europe than in the UK, where three-axle tractors and 44-tonnes gcw predominate.

This XF bristles with equipment that will bring smiles to the faces of many UK transport managers, finance directors and drivers alike.

There is nothing old-fashioned about the XF’s 10.8-litre, MX-11 engine. It went into production five years ago and has earned a reputation as a highly fuel-efficient, flexible and reliable power unit.

Last year the engine was tweaked as part of the latest CF and XF rejig which is claimed to deliver an overall fuel economy gain of up to 7%.

Engine speed has been cut slightly and power and torque boosted to compensate.

In the XF I drove the maximum power rating is 330kW at only 1,600rpm, with generous peak torque of 2,300Nm at 900-1,125rpm.

The engine drives through the excellent 12-speed ZF TraXon automated manual gearbox to the latest Daf single-reduction drive axle with a tall ratio of 2.38:1.

The net result, with a loaded tri-axle boxvan semi-trailer taking gross combination weight to around 36 tonnes, is a relaxed drive, with exceptionally low interior cab noise levels at cruising speeds, even by today’s high standards.

But the three stand-out features of this particular truck are its superb Jacobs engine brake – highly effective at low engine speeds and backed up here in a belt and braces move with a ZF Intarder hydraulic retarder – plus the options of Silent Mode and a Night Lock.

The Silent option is available throughout the Daf range (LF, CF and XF) and is designed to lower exterior truck noise levels enough to meet limits for deliveries in urban areas at night.

Just a push of a button activates the system. The engine’s electronic control unit then lowers engine speed and torque.

More than this, the gearbox is encapsulated in additional noise-absorbing material and its shift control software is adapted so that shifts are made at lower engine speeds, thus cutting noise emission further.

Engaging Silent mode is said to cut exterior noise from the truck to below a whispering 71 dB(A). My experience with this XF 450 FT Silent leaves me confident in the veracity of that claim.

The XF cab may be the oldest on the market but the Night Lock option surely can make it one of the most secure.

It was developed in response to a spate of truck robberies in which villains forced open cab doors while the driver was asleep inside.

Daf’s well-thought-out answer is a stout additional mechanical lock mounted on the cab’s sidewall. A hardened steel pin slides into the door armrest when the lock is activated.

Ease of use was a crucial consideration so a driver can escape quickly in an emergency. One press of a red button disengages the lock.

Model tested: Daf XF 450 FT Silent