First drive: Twin-turbo diesel spices up Volvo XC60
BY JAMES STANFORD | 3rd Dec 2009
VOLVO is introducing a new high-performance twin-turbo D5 diesel on three of its large vehicles – the XC60, XC70 and S80 – replacing the previous single-turbo D5.
Volvo’s smaller cars, the C30, S40 and V50, have switched from the D5 to a more basic and more affordable 2.0-litre four-cylinder turbo-diesel.
The all-new D5 engine was developed over three years, and shares no major components with its predecessor.
It produces 151kW of power at 4000rpm and 420Nm of torque from just 1500rpm through until 3250rpm.
The 2.4-litre in-line five-cylinder has a long stroke, twin overhead camshafts and an aluminium cylinder head and block.
A common-rail fuel injection system with piezoelectric injection pumps fuel in at 1800 bar for better combustion.
For greater response, the turbochargers operate sequentially, with a small turbo spooling up at lower speeds, while a larger turbo operates at high speed. Boost pressure is up to 1.8 bar.
Volvo says the twin-turbo system also reduces the temperature of recirculated gasses to reduce nitrogen oxide emissions.
The D5 features ceramic glow plugs that can reach 1000 degrees in just two seconds and can hit a maximum temperature of 1300 degrees.
Volvo engineers designed the new D5 engine to suit a wide range of vehicles with little modification.
They also worked hard at a mounting system to limit noise and vibration, and also added a third stabilising rod.
Interestingly, the new D5 engine does not have a dip stick. Drivers and mechanics instead check the oil level by using the vehicle’s on-board computer.
The new D5 engine is teamed with the standard six-speed automatic transmission and linked to a Haldex all-wheel-drive system on all three vehicles.