The inspected 2008 E-Class manual lists 8.5 litres for an E320 CDI oil change including the filter. For a DPF-equipped car, its oil table lists MB 228.51, 229.31 and 229.51. This guide covers the W211/S211 OM642.920 V6; confirm your vehicle instructions and permitted SAE grade before purchasing.
Coverage: E320 CDI V6 W211 saloon and S211 estate with the 2,987 cc OM642.920 engine, 165 kW / 224 hp. MANN catalogues this application from May 2005 to December 2009. These are application dates, not UK registration cut-offs. Earlier OM648 straight-six, petrol E320, BlueTEC and 4MATIC applications are outside this guide.
The documented quantity and approval
| Question | Reference for the covered V6 |
|---|---|
| Replacement quantity including filter | 8.5 litres |
| DPF-equipped oil row | MB 228.51 / 229.31 / 229.51 |
| Non-DPF row | Broader country-specific list; do not transfer it to a DPF-equipped car |
| Named buying candidate | Mobil 1 ESP 5W-30 with its stated MB-Approval 229.51, where the SAE grade is permitted |
The Mercedes capacity heading explicitly includes the oil filter. It is a replacement reference, not the amount to add when the level is low. Match the model column as well as the unit: litres and US quarts are different quantities.
Search results for “E320 CDI oil capacity” can combine the earlier 3.2-litre straight-six, this 3.0-litre V6 and other markets. This figure comes from the inspected E-Class manual’s own E320 CDI entry; sharing an OM642 family name with another Mercedes is not its evidence.
Establish whether a DPF is fitted
The manual separates diesel oil requirements by particulate-filter equipment. Its non-DPF list also includes 229.3 and 229.5 and is marked as country-specific. Those additional options do not become routine choices for the DPF branch.
Use the vehicle information and appropriate inspection to resolve uncertain equipment. Registration year alone, an online seller’s broad compatibility list or the absence of a dashboard warning does not settle the question.
MB 229.51 appears in both inspected diesel rows. That makes it a practical specification to check on a named product; it does not remove the need to match the formulation, SAE grade and applicable instructions.
Mobil 1 ESP 5W-30: a relevant buying option
Mobil’s current UK page lists Mobil 1 ESP 5W-30 with MB-Approval 229.51. This is the direct match used here, where the car permits that viscosity. Mobil also lists 229.52, but that is not a reason to assume every product carrying a newer number is interchangeable.
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Search Amazon for Mobil 1 ESP 5W-30This opens a search, so check the individual result’s exact ESP product, grade, approval declaration, seller and total volume. Similar packaging and the Mobil 1 name alone do not establish the required oil.
Buying enough without overfilling
Two four-litre containers total eight litres, below the nominal 8.5-litre replacement reference. Compare available combinations totalling at least 8.5 litres, such as five plus four litres or two five-litre containers. Check delivered prices rather than assuming one pack size is always better value.
The purchased amount is not an instruction to pour in nine or ten litres. Use the correct filling and level-checking procedure for the car, and retain any surplus clearly labelled. If the level reading is uncertain, resolve it before adding more oil.
A top-up purchase may require much less. Check the existing oil specification and the required addition rather than treating the service capacity as a top-up amount. Keep the actual oil details with the invoice for the next purchase.
Keep approval, grade and filter selection separate
A viscosity such as 5W-30 describes one property; it is not a substitute for the MB approval. Equally, a correctly approved bottle does not identify the oil filter. MANN lists HU 821 x for the covered V6 application; our E320 CDI filter guide explains that reference and the air, cabin and fuel-filter distinctions.
A receipt saying only “fully synthetic oil” leaves an avoidable gap. Retain the exact product and approval, pack label or product information, date and mileage. Use the E320 CDI maintenance guide to organise that record alongside other work.
Find more models in the Mercedes maintenance hub. For a separate fault-reading or tool question, browse our Mercedes diagnostic scanner guides and check the exact diesel vehicle and required function.
Sources and checks
- Mercedes 2008 E-Class manual, printed pages 386–387 / PDF pages 389–390: DPF rows, country footnote and replacement capacity.
- Mobil UK: Mobil 1 ESP 5W-30: current approval declaration.
- MANN HU 821 x application catalogue: exact E320 CDI V6 engine entry.
Research checked 20 October 2026. The Mercedes-hosted English 2008 manual covers saloon and estate but carries a German-market online disclaimer. Match it to the manual, Service Booklet and supplements supplied with your car; it does not establish every UK build’s complete service schedule.
