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RTC644240 - Piston Assembly Engine Part Land Rover Range Rover

RTC644240 - Piston Assembly – +0.040in Oversize

- €57,50
€57,50
€57,50 - €57,50
€57,50
Aftermarket Part
Aftermarket: Quality alternative. This is a quality alternative, designed to fit and function like the original part, often at a more competitive price.
Piston Assembly for the 2.5 four-cylinder naturally aspirated diesel, machined +0.040 in oversize.

The piston transfers combustion pressure to the connecting rod through the gudgeon pin and carries the ring pack that seals the bore and controls the oil film. Crown and ring-land geometry set the compression height and combustion bowl shape for this engine, so pistons are matched to the block rather than interchanged between diesel variants.

+0.040 in oversize is used where the cylinder block has been rebored to that step during a rebuild; the bores must be machined and honed to suit before fitting. Piston protrusion above the deck and ring end gaps should be checked against the engine specification during assembly.
Vehicle Model Land Rover Defender up to 2016
Fitment Notes DEFENDER 1987-2006 — 2.5L 4-cyl naturally aspirated (NA) diesel, piston assembly, +0.040in oversize
Alternative Codes
RTC644240

Available to order 2–3 weeks

Not currently in stock. Order now — typically ships within 2–3 weeks.

Need it faster? Contact us about express import (2–5 business days).

When will my order arrive?

This item is ordered from our supplier on request. Typical lead time is 2–3 weeks from order confirmation.

  • Netherlands / Belgium / Germany: 2–4 working days after dispatch.
  • Other EU countries + UK: 4–8 working days after dispatch.
  • Outside EU/UK: contact us for an estimate.

Need it faster? Express import available in 2–5 business days — contact us before ordering.

Job kits containing this part

This part is included in 0 job kit(s) below. Pick the kit that matches your vehicle and job, then add what you need.

Frequently asked questions

What is the RTC644240 piston assembly?
The RTC644240 is a piston assembly at +0.040 inch oversize for the 2.5 litre naturally aspirated diesel engine. It typically comes as the piston with rings and gudgeon pin for a reground cylinder bore. This is the oversize service size.
What does +0.040in oversize mean and when do I need it?
The +0.040 inch oversize means the piston is machined larger than standard to suit a cylinder bore that's been rebored 0.040 inch. You need this size only if your engine block has been machined to that oversize. Check the rebuild spec before ordering.
Which engine does this piston fit?
This piston assembly fits the 2.5 litre four cylinder naturally aspirated diesel used in the Land Rover Defender from 1987 to 2006. It's specific to the NA diesel, so confirm you don't have the turbo diesel or Td5 before ordering.
How many pistons do I need for the engine?
A four cylinder engine typically needs four pistons for a full rebuild, so you'll usually order this in a set of four all at the same oversize. Mixing sizes across cylinders isn't done. Check each bore has been machined to +0.040 inch.