From one simple turbo to two working in sequence
The older four- and five-cylinder diesels keep things simple. A 300Tdi breathes through an AlliedSignal (Garrett) T25, and the Td5 through a Garrett GT2052S shared by its Defender and Discovery tunes. When the Defender moved to the Ford Duratorq Puma engine in 2007, it gained a variable-geometry turbo and torque rose from 300 Nm to 360 Nm.
The V6 and V8 diesels are where it gets involved. The 2.7 TDV6 uses one large variable-geometry turbo chosen for low-speed pulling power, the 3.0 SDV6 pairs a variable-geometry primary with a second turbo that joins at higher revs, and the 3.6 TDV8 runs two variable-geometry turbos at up to 1.6 bar of boost. A quote for any of them depends on knowing exactly which arrangement you have.