With the I-Shift, Volvo Trucks has turned the spotlight on the transmission on the international truck stage. Never before has a transmission received such a positive response from drivers and transport companies all over the world.
Today 60 per cent of all Volvo FH trucks are sold with I-Shift and it is standard in the world’s most powerful series production truck, the 700 hp Volvo FH16. Sven-Erik Tibb, chief project manager for the development of the I-Shift at Volvo Powertrain, tells the story behind the I-Shift….
What drove the demand for a new transmission ?
“The I-Shift’s predecessor – Geartronic – was not an optimised solution and an automatic transmission was needed to enhance driver comfort and driving ease. At the same time, the development of electronic systems really took off at the end of the 1990s. More and more of these improved systems were used to control both the engine and the rest of the truck and this created new opportunities to develop an electronically controlled transmission.”
So what was your assignment ?
“The target was to produce a so-called ‘automated mechanical transmission’ (AMT) aimed at European long-distance and distribution vehicles with a maximum weight of 40 tonnes. The prerequisites were improved functionality, reliability; smooth gear-shifting and economical driving.”
When did the work begin ?
“At the end of 1998, but, prior to that, we conducted an in-depth pre-study in which we discussed and analysed different concepts and technical solutions. We examined not only the technology but also production and the best total solution. So, when we started the project, we knew what we were aiming for.”
What was the greatest challenge ?
“Firstly, to design a control system for the transmission; in other words, the system that was going to perform the gear-shifting in the form of electronics, valves, cylinders, sensors and the actual software. All of this then had to be combined with the mechanical systems. What’s more, the transmission had to be unsynchronised and this imposed unique demands on the design. We completed this assignment very successfully, but it was really hard work.”
What was the secret ?
“First and foremost, the pre-study, which laid the foundations for a successful start. In addition, many skilled people were involved in the project. During the three and a half years it took to complete the project, most of our department was involved and, at most, this comprised 30 people. More than 150,000 working hours were spent on the project.”
Where did the name come from ?
“It came at a later stage and it is Volvo Trucks’ name. There were a number of discussions about the name that should be given to the product, but we didn’t come up with the name. It was known as the P4200 when we were working on it. The name I-Shift is a combination of ‘I shift’, as in ‘I change gear’, and ‘intelligent’ shift.
How has the I-Shift developed from the first version ?
“The first phase took place in 2002, when the most important developments were made to the centre of the transmission, with a new control system and basic gearbox. Stage two, which took place at the end of 2005, involved the development of the front end of the gearbox, including the clutch system. We also extended the applications for the I-Shift, by making it available for trucks with 16-litre engines and a higher maximum weight, for example. Developments are still taking place continuously, as we introduce new products.”
How does it feel when the I-Shift is praised by drivers all over the world ?
“It feels great and it’s really satisfying. People involved in product development spend a great deal of time solving problems and so it’s especially pleasing to see results. When a project is as long as this one, it takes several years before you see the results and receive feedback from drivers. So it’s fantastic to see how much appreciation our work has generated.”
Are you proud of your creation ?
“Well, I have to begin by pointing out that this is not simply my creation. It has been produced by the entire organisation. It is the result of tremendous teamwork and is definitely not the work of one person. All of us are incredibly proud when we see how good the I-Shift is. We are working the whole time to maintain our existing products in order to develop even better solutions in new projects.”
If you are honest, can the I-Shift be improved that much ?
“It is already outstanding, but that doesn’t mean we can relax and sit back. We product developers never give up and adapting the I-Shift to more and more demanding driving is a constant challenge. What’s more, the competition spurs us on the whole time and there is always someone breathing down our necks.”
- Mr I-Shift is….Sven-Erik Tibb, 52
Family : Wife, Kristina, and children, Alvina, 15, and Anton, 20
Job : Section manager at product development Volvo Powertrain, Drivelines & Hybrids
Home : Göteborg
Drives : Volvo V70 Biofuel
Hobbies : Golf and cooking
- The I-Shift is…
- Simply the best
Improved fuel consumption, smoother gearchanges and improved comfort and safety. This is how Volvo’s intelligent I-Shift gearshifting system works.
- Main section
The main section contains three base ratios, an integrated splitter, and reverse gears. The splitter and range gears are synchronised, while the base unit has no mechanical synchromesh. Instead, revs are synchronised with the help of the engine’s – and the transmission’s – control units before the next gear is engaged. This results in a faster gear change.
- Oil change
Long oil change intervals mean lower operating costs and reduced environmental impact. When special oil is used, the maximum oil and filter change interval is 400,000 kms or every third year.
- Manual & automated
Gearchanging can be done manually or automatically. ‘Performance’ mode gives maximum power and best drivability in automatic, while ‘Economy’ mode gives priority to low fuel consumption. In manual operation, gearchanging is done with a button on the gear lever.
- Clutch control
The clutch is automatic and is operated with compressed air. The clutch control unit is integrated into the gearchanging system and has only one air connection. Due to the high performance of the I-Shift transmission, no clutch pedal is needed.
- High reliability
The gears in the base unit are made of case-hardened steel and are helical, so more teeth can mesh at any one time – the result is quiet operation and high reliability.
- Gear control
The gear selector has no mechanical contact with the gearbox. Instead, movement of the gear lever, which is integrated into the driver’s seat, activates sensors in the gear selector. The gear control system, integrated into the base unit, contains an electronic control unit, solenoid valves, gear-changing cylinders, shift forks and sensors.
- VEB/VEB+ and brake assist
The I-Shift is developed together with the engine and Volvo engine brakes (VEB/VEB+). With 16 litres of displacement, VEB+ provides an impressive maximum braking effect of 425 kW. For applications where also a retarder is needed, the gearbox can easily be combined with the Volvo compact hydraulic retarder with a braking power up to 400kW.
- New additions to the I-Shift in 2009
- Increased comfort and fuel saving for heavy transportation. A driver hauling a heavy load one way and returning empty the other can conveniently switch between two gearchanging programs.
- Improved freewheel function. Saves even more fuel. Activated automatically when neither engine power nor engine braking is needed.
- The updated I-Shift transmission gives improved functionality on soft grounds, found in construction and timber segments, via the P+ performance mood that optimize gear shifting for these applications.
- Faster declutching. Makes it easier for the driver to rock the truck out of difficulty if it gets bogged down.