Layout
Configuration	60° V6
Displacement	2,099 cc (128.1 cu in) 2,495 cc (152.3 cu in) 2,967 cc (181.1 cu in)
Cylinder bore	81.6 mm (3.21 in) 89.0 mm (3.50 in)
Piston stroke	66.8 mm (2.63 in) 79.5 mm (3.13 in)
Cylinder blockalloy	Aluminum
Cylinder headalloy	Aluminum
Valvetrain	DOHC
Compression ratio	10.3:1 10.75:1
Combustion
Fuel system	Sequential multi-port fuel injection
Fuel type	Gasoline
Oil system	Wet sump
Cooling system	Water-cooled

The Jaguar AJ-V6 engine is a specialized version of Ford's Duratec engine. One notable addition is the use of variable valve timing, a feature also shared with Mazda's version of the engine. It is available in 2.1 L, 2.5 L and 3.0 L displacements.

Jaguar's AJ-V6 engine has an aluminium engine block and aluminium DOHC cylinder heads. It uses SFI fuel injection, has 4 valves per cylinder with VVT, features fracture-split forged powder metal connecting rods and a one-piece cast camshaft and has direct-acting mechanical bucket (DAMB) tappets, these design aspects differentiating the AJ-V6 from the Ford and Mazda versions.

AJ20

The AJ20 2.1 L (2099 cc) version has an 81.6 mm (3.2 in) bore and 66.8 mm (2.6 in) stroke. Although it displaces nearly 2.1 litres, it is marketed as a "2.0". It produces 157 hp (117 kW; 159 PS) and 148 lb⋅ft (201 N⋅m). The compression ratio is 10.75:1.

This engine is used in the following vehicles:

Jaguar X-Type 2.0 (UK)

AJ25

The AJ25 is a 2.5 L (2495 cc/152 in³) version built in Ford's Cleveland, OH #2 factory. It shares the 2.1's 81.6 mm (3.2 in) bore and is stroked to 79.5 mm (3.1 in), the same as the 3.0. It delivers 192 hp (143 kW; 195 PS) at 6800 rpm with 178 lb⋅ft (241 N⋅m) of torque at 3000 rpm from 10.3:1 compression.

This engine is used in the following vehicles:

2001-2009 Jaguar X-Type 2.5, 194 hp (145 kW; 197 PS) and 180 lb⋅ft (240 N⋅m)

2002-2006 Jaguar S-Type 2.5 (UK), 201 hp (150 kW; 204 PS) and 185 lb⋅ft (251 N⋅m)

AJ30

The AJ30 is a 3.0 L (2967 cc) version and is the most common, especially considering the Duratec 30. It has an 89 mm (3.5 in) bore and shares the 2.5's 79.5 mm (3.1 in) stroke. In the X-Type, it produces 231 hp (172 kW; 234 PS) and 209 lb⋅ft (283 N⋅m). The Jaguar XF debuted a refined version of the AJ30 with continuously variable cam-phasing and variable geometry air intakes to increase power and broaden the powerband up to its 6800 rpm redline.

This engine is used in the following vehicles:

2000-2008 Jaguar S-Type, 240 hp (179 kW; 243 PS) and 216 lb⋅ft (293 N⋅m)

2002-2009 Jaguar X-Type, 231 hp (172 kW; 234 PS) and 209 lb⋅ft (283 N⋅m)

2009-2011 Jaguar XF 240 hp (179 kW; 243 PS) and 221 lb⋅ft (300 N⋅m)

2000-2005 Lincoln LS