Reference specification for the 3.0‑litre straight‑six Ingenium diesel (AJ20D6), fitted to modern Land Rover and Jaguar models. No opinions — just the verified numbers and variant‑specific caveats.
The AJ20D6 (3.0‑litre Ingenium straight‑six diesel) takes approximately 7.4 litres of oil with a filter change [PLACEHOLDER — confirm vs OEM workshop data], using a low‑SAPS 0W‑20 or 5W‑30 viscosity oil meeting JLR specification STJLR.03.5006 or similar.
Full specification table, variant differences, common mistakes and the oil‑dilution caveat explained below.
| Spec | Value |
|---|---|
| Capacity with filter change | ~7.4 litres [PLACEHOLDER] |
| Capacity without filter change | ~7.0 litres [PLACEHOLDER] |
| Viscosity grade | 0W‑20 or 5W‑30 (low SAPS, depending on market) |
| JLR specification | STJLR.03.5006 / 5007 [PLACEHOLDER — confirm exact spec] |
| Change interval | 16,000 miles / 12 months [PLACEHOLDER] |
| Oil filter type | Cartridge, top‑mounted |
Figures marked [PLACEHOLDER] require confirmation against the OEM workshop manual before this page goes live — flagged here deliberately rather than guessed.
The AJ20D6 is fitted across a range of JLR models. While the core oil capacity is consistent, sump design and filter access vary slightly by application.
| Application | Capacity Note | Filter Access |
|---|---|---|
| Defender (L663) | Standard 7.4L figure applies | Top‑mounted, accessible with engine cover removed |
| Range Rover (L460) | Standard figure, some early builds noted slight variance | Top‑mounted, tight access on V8 models but sufficient |
| Range Rover Sport (L461) | Standard figure applies | Top‑mounted |
| Discovery 5 (L462) | Standard figure, same as Defender | Top‑mounted |
| Velar D300 (AJ20D6 variant) | Standard figure | Top‑mounted, slightly tighter but accessible |
| Jaguar XF / F‑Pace (same engine) | Standard figure | Top‑mounted, different engine bay layout but same filter |
The manufacturer's 16,000‑mile service interval assumes normal use with a healthy mix of motorway and urban driving. In real‑world UK conditions – particularly short urban journeys – the DPF regeneration process can introduce unburned fuel into the oil, leading to dilution. This is a well‑documented characteristic of the Ingenium family [EM-INTERVIEW], and the AJ20D6 is not immune. Many independent specialists recommend a 6,000‑mile oil change interval for vehicles used predominantly for short trips, regardless of the service computer indication. This practical adjustment costs a fraction of a major repair and is widely adopted by workshops that see these engines regularly.
For a deeper look at oil dilution and its consequences, see our Ingenium oil dilution failure page.
The oil filler cap and dipstick (if fitted – some later models have electronic level monitoring) are clearly marked and accessible from the top of the engine bay. Confirm your exact engine code by locating the engine number stamp – see our Engine Number Location guide. Early and late production runs of the AJ20D6 may have minor running changes affecting oil specification; always refer to the latest JLR service bulletin for your VIN.
Using the correct oil grade and low‑SAPS approval is not optional on the AJ20D6. The engine's high‑pressure common‑rail system, turbocharger, and emissions after‑treatment are all sensitive to oil viscosity and ash content. Incorrect oil can lead to increased wear, DPF blockage, and potentially expensive repairs – far exceeding the cost of proper maintenance. The 0W‑20 or 5W‑30 grade is chosen for its cold‑start flow characteristics, protecting the engine during the critical warm‑up phase on cold UK mornings. For a full breakdown of the failure modes linked to poor oil maintenance, visit our AJ20D6 early‑build issues page.
Every Figure SourcedUnverified numbers are flagged, never guessed.
Last Verified February 2026Reviewed on a regular schedule, not left to go stale.
12 Vetted JLR SpecialistsReal workshop insight behind the caveats, not just the spec sheet.
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