Published on February 12th, 2020 | by Subhash Nair0
BMW X5 and X6 to Get New Inline 6 Diesel Mild Hybrid Powertrain
Dieselgate is officially a thing of the past and BMW is now right back into it, with this new and improved B57 diesel straight 6 that has been paired to a 48V mild hybrid system on their new X5 and X6 SAVs. The xDrive40d on both of these models will be equipped with this powertrain.
B57 Diesel in a high state of tune
The B57 is also equipped on xDrive30d variants of these SAVs. In that model, its output was 261hp and 620Nm of torque. Here, the output is 340hp and 700Nm of torque from the engine alone. The engine features:
- two-stage turbocharging system
- Common Rail piezo direct fuel injection
- A new pressure sensor integrated into the injector
- Further developed two-stage NOX exhaust gas treatment (now comprises an oxidation catalyst converter and an SCR coating on the particulate filter)
- Second dosage unit has been integrated at the outlet of the SCR system
Mild Hybrid System
A 48V starter-generator has been outfitted. It produces just 11hp but helps both SAVs get from 0-100km/h in just 5.5 seconds and reduces fuel consumption in normal driving modes.
Here’s the press release with more.
The BMW X5 and the BMW X6 now also feature highly efficient mild hybrid technology to optimise the spontaneous power delivery and effectiveness of the drive system. As from May 2020, the new BMW X5 xDrive40d (combined fuel consumption: 6.4 – 5.9 l/100 km; combined CO2 emissions: 167 – 154 g/km) and the new BMW X6 xDrive40d (combined fuel consumption: 6.2 – 5.8 l/100 km; combined CO2 emissions: 164 – 153 g/km) will boast a newly developed straight six-cylinder diesel engine with a 48-volt starter generator. Thanks to the power output of the combustion engine being increased to 250 kW/340 hp, and the electrically assisted mild hybrid system, the superior forward thrust of the luxury-class Sports Activity Vehicle (SAV) and Sports Activity Coupe (SAC) is experienced even more intensively.
Sporty and agile handling on the road as well as robust off-road versatility are hallmarks of the driving characteristics of the BMW X5 and the BMW X6. With the strong presence of its powerful and elegant design and a luxurious interior ambience also in the current model generation, the two founders of each of their segments make an impressive statement. Moreover, high-quality comfort features and advanced technology in the areas of operation and digitalisation contribute towards the driving pleasure experienced in the two BMW X models. The latest innovations in the field of drive technology now complement the engine portfolio of the SAV and the SAC with a diesel engine combining pulling power and efficiency in a particularly convincing manner.
Straight six-cylinder diesel engine with multi-stage turbocharging and optimised direct fuel injection.
The BMW TwinPower Turbo Technology featured by the new 3-litre straight six-cylinder power plant comprises a two-stage turbocharging system and Common Rail piezo direct fuel injection. The spontaneous response characteristics of the supercharging system are enhanced by variable turbo geometry for the high and low pressure stages. With up to 10 injections per cycle, the injectors feed fuel to the combustion chamber at a pressure of up to 2,700 bar. The new pressure sensor integrated into the injector ensures exceptionally precise dosing as well as favourable fuel economy and clean combustion.
The new diesel engine develops a maximum torque of 700 Nm becoming available between 1,750 and 2,250 rpm. The engine achieves a maximum power output of 250 kW/340 hp at 4,400 rpm. Whether on the road or on off-road terrain, power is transferred in the new BMW X5 xDrive40d and the new BMW X6 xDrive40d via an 8-speed Steptronic transmission and intelligent BMW xDrive four-wheel technology, which – thanks to a rear-wheel accentuated set-up – enhances agility during dynamic cornering.
Two-stage NOX exhaust gas treatment, which was introduced as a standard feature on diesel models in 2012, has been further developed. This component, which is close to the engine, now comprises an oxidation catalyst converter and an SCR coating on the particulate filter. For optimum reduction of nitrogen oxide emissions a second dosage unit has been integrated at the outlet of the SCR system. Therefore, the new BMW X5 xDrive40d and the new BMW X6 xDrive40d now already comply with the mandatory regulations of the Euro 6d emission standard, which will not take effect until the beginning of 2021.
Mild hybrid technology: Additional electric output of 8 kW/11 hp increases sprinting power whilst reducing consumption.
The new diesel engine is assisted by the 48-volt starter generator of the mild hybrid system. The additional electric output of 8 kW/11 hp promotes both spontaneous power delivery and effectiveness of the drive system. Electric boost enhances dynamics when starting and accelerating. Therefore, the new BMW X5 xDrive40d and the new BMW X6 xDrive40d are each able to sprint from 0 to 100km/h in just 5.5 seconds. Thanks to the additional electric output, the combustion engine is able at constant speeds to run particularly frequently within an efficiency-optimised load range, thus reducing consumption peaks.
The starter generator obtains the necessary energy from the 48-volt battery, which also supplies all electric driving functions with power via the 12-volt vehicle electrical system. It is charged by means of recuperation during acceleration and braking phases and also through a targeted combustion engine load point increase. Ride comfort also benefits significantly from the mild hybrid technology featured in the new BMW X5 xDrive40d and the new BMW X6 xDrive40d. The supportive effect of the 48-volt starter generator facilitates extremely fast and comfortable load change responses. Moreover, the powerful generator provides for spontaneous and low-vibration starting and re-starting of the combustion engine when using the Auto Start Stop and “sailing” functions. As a result, it is also possible to not only disconnect the engine during the sailing phases, but also to switch it off entirely. In order to make use of the economising effect as frequently as possible, the comfort-optimised sailing function is now no longer only available in the ECO-PRO mode, but also in the COMFORT mode of the Driving Experience Control feature.