V8 EngineAJ-V6/AJ28
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Introduction
The AJ28 engine is a variant of the 4.0L 90û V8 units fitted to the XJ and XK range of vehicles. The AJ28
shares some of the changes incorporated in the current AJ27 engine: both engines are derived from the
original AJ26 unit. A number of features are unique to the AJ28 or are shared with the AJ-V6 engine also
described in this publication.
Features of the AJ28 engine are:
¥ Continuously variable inlet valve timing over a 48û
+
-2û crank angle: as fitted to the AJ27 engine
¥ Full authority cable-less electronic throttle control: as fitted to the AJ-V6 engine
¥ Air assisted fuel injection: similar to system used on the AJ27 engine
¥ Unique induction manifold with centrally mounted throttle body
¥ Returnless fuel system: similar to AJ-V6 engine
¥ Twin wall exhaust manifold
¥ Engine management system as used on the AJ-V6
¥ New sensors
¥ Modified sump and oil cooler
¥ Modified front end ancillary drive and components
Engine Specification
Maximum power DIN - 209 kW (281 BHP) at 6100 RPM
EEC - 203 kW (276 PS) at 6100 RPM
Maximum torque DIN - 390 Nm (287 lbft) at 4300 RPM
EEC - 278 Nm (279 lbft) at 4300 RPM
Oil Specification
All markets except the USA and Canada
Engine oil for all markets except the USA and
Canada must be to API specification SJ/ACEA A1
or A3.
The recommended SAE viscosity for different
ranges of ambient temperature are shown in
table 1.
USA/Canada
Engine oil for USA and Canada must be to API
specification SJ/ILSAC GF-2.
The recommended SAE viscosity for different
ranges of ambient temperature are shown in
table 2. For maximum economy and in most
climate conditions, SAE 5W/30 is to be preferred
but SAE 10W/30 or 15W/40 are acceptable in
moderate to hot climates.
JOL.29550
50JOL.296
SAE/TEMPERATURE TABLE 2
SAE/TEMPERATURE TABLE 1
