Technical details
| Make & model | Iveco Daily 55S17W Euro VI 4×4 |
| Year | Built: 2016 / First registration: 2017 |
| Wheelbase | 3400 mm |
| Tyres | 5 x Michelin XZL 255/100R16 5 x Kraiburg K51 (all-terrain profile) retreads on Michelin XZL carcass |
| Max. gradeability | 45°/100% |
| Approach angle | 49° |
| Departure angle | 32° |
| Static flip angle | 48,9° |
| Wading depth | 660 mm |
| Gross vehicle weight | 5,5 tons |
| Reinforced rear springs | 4 leaf parabolic springs – linear characteristic |
| Engine | 3.0 L Euro VI diesel 16 valves |
| Power Kw/Hp / Rmin | 125/170 / 3000-3500 |
| Torque / Rmin | 400 Nm / 1250-3000 |
| Exhaust gas treatment | EGR / SCR / DPF |
| Fuel tank | 90L standard + 160L custom made tank 3 x 20L jerrycans attached to the rear of the chassis |
| AdBlue tank | 25L |
| Gear box | 6 speed |
| Transfer box | On road High/Low – Off road High/low |
| Gears | 24 forward – 4 reverse Permanent four wheel drive |
| Differential locks | Hydraulic – centre & rear |
The empty chassis waiting at the bodybuilder
Subframe in galvanised steel
The cabin is mounted on a 4-point torsion-free subframe (‘Rautenlagerung’), featuring 2 pivoting axes at right angles. This type of frame makes the cabin completely independent from the twisting movements of the truck chassis underneath, especially in off-road conditions. In addition, it limits the cabin’s movements in relation to the cockpit.
A quintet of new shoes
On our 2019 Silk Road journey, after a bumpy mountain road in northeastern Turkey, we noticed a sudden abnormal wear on our truck’s tyres and a steering wheel that stood slightly out of balance. Iveco service in Trabzon couldn’t find anything abnormal. There was no clear visual indication to put a finger on these symptoms. The Iveco-people tackled the problem by balancing the wheels and interchanging two of them. The position of the steering wheel was better again, though not perfect. The wear of the tyres went on, though much more slowly and less asymmetrically.
Beginning of the mountain pass between Şebinkarahisar and Giresun (Turkey). Here the tyres were still in perfect condition. The next day, they had visibly started wearing.
Only several thousands kilometres later, after some off-road shunting and just after tackling a very steep, slanting and even slightly scary track near Naryn in Uzbekistan, all of a sudden the steering wheel skewed some 150°. There was no visual indication of anything being wrong. The truck felt completely normal and kept track perfectly when driving on asphalt again. Strange symptoms, I thought.
At MAN-service Samarkand (Uzbekistan) they immediately found out that the rear axle wasn’t properly aligned anymore. It took them thirty minutes to do the necessary and tackle the root of the problem. My conclusion: the rear axle had gone slightly out of geometry in Turkey, and suddenly a lot more on this demanding track in Uzbekistan. Probably a bolt on the left side had become too loose.
Re-adjusting the rear axle at MAN service Samarkand (Uzbekistan)
Unfortunately, big rough tyres like the Michelin XZL, when they start wearing asymmetrically, there’s no chance that interchanging (some of) them will save the tyres through counterbalancing the wear and tear. So, although there was still plenty of rubber on the profile, my beautiful and expensive soles were gone.
Buying a set of new XZLs is very expensive. Finding an adequate but affordable alternative while keeping the same rims, is quite a challenge: the XZL 255/100R16 is the only available tyre in this exact dimension. And it’s a hell of a shoe! On all of our previous journeys in the past 20 years, where we sometimes maneuvered fully loaded over the most unimaginable terrain, from the aforementioned track in Uzbekistan to the Cirque de Jaffar in Morocco, these tyres had never let us down. My first set of XZL’s lasted almost 100,000km. Even then I could have gained a theoretical 25% extra by carving the profile. Which I didn’t.
According to our travel plans, in the near future, we’ll be traveling in less extreme conditions. So, an all-terrain tyre would be fine. Additionally, it would probably result in less humming and a smoother ride on highways. We already had some pretty good experiences with the Kraiburg K75 retread profiles (very similar to the Michelins) on the old Iveco. Now we found an interesting quintet of new shoes in the form of Kraiburg K51 retreads based on a used XZL carcas
Just out of the shoebox: retreaded Kraiburg K51 tyres based on the XZL carcass.
These tyres cost less than half of the price of new XZLs. They look very well finished. Also the used carcasses do not raise any suspicion about their quality. They probably originate from military use, where tyres are often replaced while still having an 80% tread depth. The K51 profile is rough enough for not too challenging terrain. The first one thousand kilometers on regular roads resulted in a very quiet ride and no visible wear. So far, only the coronavirus was able to stop them. I’ll keep you posted as soon as I gain more experience in off-road conditions.
Origin of the poor geometry of the rear axle
The problem originated in installing aftermarket reinforced rear springs. As we didn’t like the behaviour of the original, very harsh two stage rear springs, we opted for the reinforced, Bremach type set offered by Allrad Christ in Austria. This set definitely results in a more comfortable ride and at the same time a substantially bigger payload. At least theoretically, as we kept the registered gross weight of the vehicle the same.
Reinforced leaf springs on the rear axle. Don’t forget to tighten the bolts after the first 1,000 km
Installing new leaf springs is pretty straigthforward. But, at least with this set of springs, because of the use of a slightly slanting spacer block between the springs and the axle, it’s important to tighten the bolts after the first 1,000 kilometres. Which hadn’t been done… because we didn’t know… resulting in an unaligned rear axle after our experiences in Turkey and Uzbekistan… resulting in the abnormal and quick wear of the tyres… You get the picture.
I like learning by doing. I don’t like it when, as a result, I suffer in my pocket.
Jerrycan holder at the rear of the chassis
Three 20L jerrycans reside in one single and one double standard FrontRunner jerrycan holder.
Typical for an expedition camper is the constant heavy weight on the rear axle. To provide some leeway and, at the same time, improve the driving comfort, I have replaced the standard suspension at the rear axle with reinforced leaf springs which have a more linear spring characteristic.
Another result of this intervention is that the car is now 6cm higher at the back than originally. This difference in chassis height between front and rear has proven to be very useful in practice, levelling the car longitudinally on slight inclines. When a camping spot surface is completely level, one must use a pair of wheel chocks. However, in reality the situation almost never arises that a surface is really level, especially not while camping in the wild. With the difference in height between front and rear, one can often easily level the car, even without using wheel chocks. In addition, in the case of steeper gradients one has more margin to level the car.
Making use of the difference in chassis height between front and rear