DAF’s former flagship is facing the test. The DAF XF 105 was produced from 2005 to 2013, and the years have left their tracks on this long-serving concept.
The roots of the XF 105 can be traced back to 1987 and the DAF 95. Since then, the Dutch company has continuously revised its flagship. The XF 105 is now in its third version. The concept has aged over the years, but the technology under the hood has been continually updated. It is mostly the interior and many other details that betrays the age of the XF 105. Still, it is very popular all over Europe. The likely reason for this may be its mature concept.
Spacious Driver’s Cab and New Safety Features
The Super Space Cab offers the driver a lot of living space. It offers practical features, generous storage space (also under the cot), and elbow room. Many details, such as the large, open tray in the middle of the dashboard, the fly screen in the roof hatch, or the comfortable lower cot are well-thought-out and show that DAF not only focuses on the buyer but also the driver.
The last model update brought several new safety and assist systems to the driver’s cab of the XF 105. This includes an adaptive cruise control ACC and a lane departure warning system. The company charges extra for these features—just like its competitors. The ACC of the DAF brakes with a deceleration of 2,5 m/s². This is standard among competitors and provides solid braking performance for the DAF. Activation of the ACC first activates the engine brake. This is followed by the retarder, and only then by the service brake. This explains that ACC can only be ordered in combination with the retarder. As part of the safety features, the Night Lock for the door conceals two sliding bolts in the doors, which provide an additional interior lock and which is so far only available from DAF.
Not Everything Is Positive
DAF continues to put its trust in a standing brake pedal. Drivers must first get used to that. The outside stow compartments also gave reason for complaint. Their size was sufficient, but the openings were much too small. The MX six-cylinder engine is not smooth. In addition, the air current generated at the A-beams and the high roof causes noises that cannot be ignored.
The large display between the speedometer and the tachometer could be more user-friendly as well. The red letters on the black background are hard to read. On the other hand, the engine noise stays in the background. This is due to sufficient damming in the engine compartment, because the noise level hardly increases during deceleration or during full acceleration with high rpm on a climb.
Developed by DAF, Sold as a Paccar
MX engines have been in production since 2004. Although DAF has developed the engines and manufactures them in Eindhoven, the engines are sold as Paccar MX engines and not under the DAF brand. It must hurt Dutch pride that their engine is also used as a Paccar MX by Peterbilt and Kenworth in the USA . The most powerful version of the 12.9 liter (787 cubic inches) six-cylinder engine is the MX375, which provides 510 HP (375 kW). The maximum torque of 1840 lb-ft (2500 Nm) develops between 1000 and 1410 rpm and makes it possible that 510 hp are already available at 1500 rpm and remain at a constant level up to 1900 rpm.
The long-stroke engine has a stroke of 162 mm and a cylinder bore of 130 mm. Although the engine has one-piece cylinder heads, the camshaft is located way down on the right side of the engine block and controls not only a total of 24 valves but also builds up the pressure in the single injection pumps. The exhaust manifold and the turbo-charger housing are made up of a single cast part, which is a special feature of the MX engine. This may be practical during assembly, but will definitely be expensive if the turbocharger fails.
Brisk Driving in spite of Long Gear Ratio
The test vehicle checks in with a long axle drive ratio of 2.69 to 1, which makes for a low 1250 rpm at a speed of 53 mph (85 km/h ). This allowed the XF105.510 to move briskly along the test track. The gear shifts also worked well. What was noticeable in this test was the gearshift strategy of DAF, which has changed from a certain tendency of athleticism towards more economy. The automatic transmission shifts up earlier than before and waits longer before shifting down. However, this takes too long in some cases. The transmission normally shifts from twelfth to eleventh at slightly more than 1000 rpm. Once the electronic system has determined the level of incline, however, it shifts again at 1200 rpm. There is still room for improvement, though. If the automatic shifted earlier from twelfth to eleventh, another downshift to tenth could be avoided.
The DAF XF 105 sports the new, twelve-speed, manual Ecosplit transmission made by XF as standard equipment. This transmission can now handle input torque of 1550 to 2065 lb-ft (2100 to 2800 Nm) and always works in direct gear. The transmission ratio spread of 15.57 is not much narrower than that of 16-speed transmissions (16.41) and the weight (without the retarder in the rear) of 616 lbs. (280 kg) is 88 lbs. (40 kg) lower. The fuel consumption of the DAF XF 105.510 does not stand out. 6.46 mpg (36.4 l/100 km) is middle of the road if performance and speed are taken into account. The only limitation is that high rpm above 1600 should be taboo.
The DAF Engine Brake Worthwhile
The power of the engine brake can be doubled for a surcharge of approx. 2 400 €. The DAF Engine Brake (DEB) is a decompression brake with a braking power of 320 kW at 2300 rpm. The standard engine brake only achieves 160 kW. In many cases, it is not necessary to add a retarder, which costs significantly more and adds another 154 to 176 lbs. (70 to 80 kg) of empty weight to the X105.
Still, a retarder—the Intarder by ZF for DAF trucks—can be useful, and not only because of the higher permanent braking force of up to 500 kW. Driving is noticeably more elegant when the cruise control and maximum speed are set during downhill driving (only +3 km/h is possible). The DAF cannot hold the set downhill speed with the quasi-single-stage DEB engine brake, or it activates and deactivates the engine brake in rather a jerky way on slight inclines. With the retarder, however, the XF105 rolls evenly and comfortably downhill.
Empty Weight of Almost 7.7 Tons
Customers who are especially sensitive to the subject of payload will see the high weight of the XF105 as a disadvantage. In standardized test specifications, the truck weighs nearly 7.7 tons. A MAN 540 weighs over 660 lbs. (300 kg) less under the same conditions, and even a Scania V8 is not heavier than the XF105. Customers who really need the high payload in the DAF XF105 should leave the spare wheel at home, install as small a tank as possible, and give up the Super Space Cab for the normal Space Cab (without high roof), which is 154 lbs. (70 kg) lighter.
The main differences between the two driver’s cabs: a lower interior height by 15½ inches (370 mm), less storage space above the windshield, and less standard equipment. The lower Space Cab (maximum interior height: 75 inches [1900 mm]) still provides sufficient space for two cots—but with restricted open space above. The strong points of the DAF XF105.510 Super Space Cab version are a large and functional driver’s cab, a powerful, although not always refined, engine, good driving performance, great driving comfort, and a mature design. The DAF still requires reworking with regard to the payload, handling, and wind noise. There is many a detail that other manufacturers handle better.
