MANN lists C 3698/3-2 engine air filters and HU 718/5 x oil filters for the CLK280 and CLK350 M272 models. NGK UK lists six PLKR7A spark plugs, stock 4288, for each. Cabin filters need an equipment check: right-hand-drive THERMATIC and THERMOTRONIC have different catalogue branches.
Coverage: CLK280 C209 coupé / A209 cabriolet with M272.940 3.0-litre V6, and CLK350 with M272.960 3.5-litre V6. Mercedes lists 170 kW / 231 hp and 200 kW / 272 hp respectively. These are petrol models; the older M112 CLK320 and OM642 CLK320 CDI have separate guides.
Engine filters and spark plugs
| Item | Manufacturer reference | Application detail |
|---|---|---|
| Engine air filtration | MANN C 3698/3-2 | Listed for both CLK280 and CLK350 M272 models. |
| Oil filter | MANN HU 718/5 x | Keep the complete reference and check seals supplied. |
| Spark plugs | NGK PLKR7A, stock 4288 | Six for CLK280 M272.940 and six for CLK350 M272.960. |
Part references establish catalogue applications, not a requirement to replace every item at every service. Check the work due and the previous replacement record before choosing a kit.
Engine air filters: C 3698/3-2
Use the full C 3698/3-2 reference when comparing listings. MANN names both covered petrol models, but the seller’s supplied contents still need checking. Do not infer a pack quantity just from a photograph or the suffix.
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Search Amazon for MANN C 3698/3-2 air filtersCheck whether the search result is the named item, a different filter or a wider bundle. A listing mentioning several Mercedes models should still identify your engine application.
Oil filter: HU 718/5 x
HU 718/5 x is MANN’s listed oil-filter reference for both models. Confirm the full number and sealing components. The CLK280 / CLK350 oil guide explains the separate 8.0-litre oil-change quantity and approval checks.
Browse oil filters on eBay, select your vehicle and check the reference and compatibility on the individual listing:
The graphic opens a category for browsing; it does not preselect a verified part for your car.
UK cabin filters: identify the climate system
| Equipment | MANN catalogue reference | What it covers |
|---|---|---|
| Right-hand-drive THERMATIC | CUK 3461/1 | Activated-carbon cabin-filter application. |
| Right-hand-drive THERMOTRONIC | CU 3461/1 | Particulate cabin-filter application. |
| THERMOTRONIC | CUK 20 000-2 | Separate activated-carbon filter application. |
MANN lists these branches for both CLK280 and CLK350. The two THERMOTRONIC entries serve different catalogue roles; do not treat every cabin-filter number as an interchangeable alternative.
For a right-hand-drive THERMATIC car, browse the named CUK 3461/1 reference below:
Search Amazon for MANN CUK 3461/1 cabin filtersConfirm the climate-control equipment before choosing that link. For a left-hand-drive import, MANN’s catalogue uses different particulate/THERMATIC references, including CU 3461 and CUK 3461. Ask a supplier to match the actual equipment if it is unclear.
Spark plugs: six PLKR7A
NGK’s current UK catalogue lists PLKR7A, stock 4288, quantity six, for each covered M272 engine. Check whether the price is for a single plug or a full set.
The older M112 CLK320 uses a different twelve-plug application, so a generic “Mercedes V6” description does not settle the count. Use the current engine-specific application and the correct fitting procedure. Establish the renewal date from the matching service information and previous invoices.
Before ordering a service kit
- Identify CLK280 M272.940 or CLK350 M272.960.
- Check each complete filter and plug reference.
- Confirm the cabin system and steering side.
- Check supplied quantities, seals and delivery costs.
- Match the oil’s approval and enough oil for the documented change.
- Agree owner-supplied parts with the garage beforehand.
Our CLK280 / CLK350 servicing guide helps plan the job and compare UK costs. Owners of the earlier engine should use the separate CLK320 M112 filter and plug guide.
Explore the Mercedes maintenance hub and our Mercedes diagnostic scanner guides for other models and fault-investigation tools.
Manufacturer sources
- MANN C 3698/3-2 — named CLK280 and CLK350 applications.
- HU 718/5 x — named CLK280 and CLK350 applications.
- CUK 3461/1: RHD THERMATIC — named CLK280 and CLK350 applications.
- CU 3461/1: RHD THERMOTRONIC — named CLK280 and CLK350 applications.
- CUK 20 000-2: THERMOTRONIC carbon — named CLK280 and CLK350 applications.
- MANN 2024–26 catalogue, printed page 212 — climate/steering branches.
- NGK UK catalogue, printed page 46 / PDF 48 — named M272 engines, PLKR7A / 4288 and six plugs.
Checked 24 October 2026. Contact Unusual Cars with corrections.
