The old 2.4-litre diesel engine will be replaced with a 2.2-litre diesel engine, but because of advances in the engine technology, it will be cleaner without losing any of the power of the larger engine.
This is good news for Defender drivers, who will expect the same torque and off-road ability made famous in the longest-running model from the luxury SUV manufacturer.
Famed for its go-anywhere ability, the new Defender will boast an improved top speed of 90mph and reduced CO2 emissions, down from 295g/km to 266g/km.
While this does not represent the top end of green SUV driving, it is a marked improvement on previous versions of the Defender and ensures it meets forthcoming EU emissions laws for all road cars.
The Defender will also be equipped with a diesel particulate filter, reducing the amount of damaging particulate emissions from the new engine.
The Defender, which is instantly recognisable because of its iconic shape, can also be improved with two new option packs for 2012 to coincide with the launch of the new engine.
The first, a Comfort Pack, focuses on improving the level of equipment in the Defender. Priced at £1650 over the asking price, the Comfort Pack adds air conditioning and a CD player to the gadgets in the cabin, while electric windows and remote central locking are also added.
The second pack, an Off-Road Pack, costs £1,500 and helps to improve off-road performance with the addition of ABS (Anti-lock Braking System) to reduce the risk of skidding, new, heavy duty tyres, a tow ball and under-ride protection bar.
As usual with the Defender, 90, 110 and 130 versions are available (the number applying to the wheelbase length of the respective cars) and a vast choice of body styles, including station wagon, double cab, chassis cab and pick-up are all available.
2012 Land Rover Defender prices start from £21,895 and the first models will go on sale in November 2011 from Land Rover dealerships.