The Mercedes-Benz GLE300d is the entry-level diesel variant of the W167-generation GLE, sold in Australia from the 2019 model year. It uses a 2.0-litre four-cylinder turbo-diesel (the OM654), a 9G-TRONIC nine-speed automatic, and standard 4MATIC all-wheel drive. Optional AIRMATIC air suspension, a full MBUX infotainment system, and a 48V mild-hybrid system on some builds add to its appeal — and its complexity. The GLE300d is a comfortable, well-appointed large luxury SUV, but it carries the running costs and occasional reliability headaches that come with any densely engineered European prestige car of this era.
OM654 Diesel: DPF, EGR and AdBlue
The OM654 is a cleaner evolution of the older OM651 and is generally well-regarded, but the GLE300d's near-2,400 kg kerb weight puts the engine and its emissions controls under constant load — especially in urban use.
DPF blockage
The diesel particulate filter (DPF) needs periodic high-temperature regeneration cycles to burn off accumulated soot. Short suburban trips — school runs, city commuting — rarely allow passive regeneration to complete. A blocked DPF triggers a yellow warning light and limp mode. A forced active regeneration at a dealership can resolve mild cases, but severe blockage requires a DPF clean or replacement at $2,500–$5,000+. Owners who regularly run the car for 30-plus minutes on an open road at highway speed avoid this issue most reliably.
EGR valve fouling
Carbon deposits accumulate in the EGR valve on the OM654 in stop-start use, causing rough idle and hesitation under acceleration. Cleaning or replacing the valve is a known service item, typically costing $400–$900.
AdBlue / SCR faults
The GLE300d's SCR system (AdBlue injection) is required under Australian ADR emissions standards. The tank needs topping up roughly every 10,000–15,000 km. More critically, faults with the NOx sensor, dosing injector, or SCR module can trigger a countdown warning that will prevent the car from restarting once it is switched off — even if AdBlue is subsequently added. Full SCR system repairs at a dealership have been reported to reach $3,000–$6,000 in parts and labour. Using a reputable AdBlue product rather than off-brand fluid is worthwhile.
Timing chain
The OM654 uses a chain, not a belt, so there is no scheduled replacement. Some owners on higher-kilometre examples report a brief cold-start rattle that clears as oil pressure builds — a potential indicator of early tensioner or guide wear. This is not a widespread failure on Australian GLE300d examples in this age range, but it merits attention on any car above 100,000 km. Correct oil grade and on-time servicing are the best prevention.
AIRMATIC Air Suspension
Many W167 GLE300d models in Australia were optioned with AIRMATIC air suspension. It delivers an excellent ride when healthy, but repairs are expensive.
- Air strut leaks: The rubber air springs can develop leaks as they age, causing a corner to sag and the compressor to run continuously. A sagging corner or "suspension inoperative" warning are the key signs. Individual air strut replacement at a Mercedes dealership typically costs $2,000–$3,500 per corner.
- Compressor failure: A leaking strut places the compressor under constant load. Secondary compressor failure adds $800–$1,800 in parts and labour.
- Sensor and valve block faults: Level sensors and valve blocks can trigger warning messages without the struts themselves failing. Proper diagnosis via Mercedes-specific tooling is essential before ordering parts.
9G-TRONIC Transmission
The 9G-TRONIC is generally capable but some owners of early W167 builds report low-speed shudder or slight hesitation pulling away, typically linked to torque converter clutch behaviour. A transmission software update from the dealer addresses many of these symptoms. Harsh downshifts when slowing can indicate valve body solenoid wear. Mercedes markets the transmission fluid as "lifetime", but independent specialists often recommend a fluid service at around 60,000–80,000 km ($300–$600) to maintain shift quality on higher-mileage examples.
MBUX, Electrics and 12V Battery
The W167 was among the first Mercedes models with MBUX, and early software had real-world issues. Screen freezing, spontaneous reboots, unreliable voice recognition, and Bluetooth dropouts have all been reported by owners internationally and on Australian forums. Most of these faults have been addressed through successive dealer software updates, so any persistent MBUX problem should start with a dealer software check.
The 12V auxiliary battery is a recurring weak point. The GLE300d's always-on electronics — MBUX modules, telematics, and the 48V system's management electronics — create a sustained parasitic drain on the 12V battery. Some owners find the car fails to start after sitting unused for several days. Replacement with an OEM-spec AGM battery costs roughly $300–$600 fitted and is a straightforward fix.
On builds with the 48V mild-hybrid system, the 48V lithium-ion battery and DC/DC converter can fail and trigger a "48V Battery Malfunction" warning. Beyond the warning itself, a failing 48V system increases load on the 12V battery and can cause further electrical anomalies. Replacement of the 48V battery assembly typically costs $1,500–$3,000 at a dealership.
Recalls & Safety Notices
The W167 GLE has been the subject of several confirmed Australian recalls registered with the government's vehicle recalls authority. Two are directly relevant to 2019–2020 GLE300d owners:
- Transmission software (REC-005922): A software fault in the transmission control module could cause the gearbox to fail to downshift, resulting in sudden loss of engine power. Remedy is a free dealer software update. This recall covered GLE and GLS (167 series) vehicles built from 2019 to 2023.
- 48V wiring harness fire risk (REC-005948): A manufacturing fault could allow the threaded nut securing the 48V wiring harness under the driver's seat to loosen. The resulting electrical resistance increase, combined with high current, created a fire risk. Remedy is a free inspection and fastener rectification at a dealership. This covered 2019–2022 GLE and GLS vehicles.
Check the Carify recall pages for the 2019 GLE300 and 2020 GLE300 for the full list of safety notices by year. You can also browse all models on the recalls landing page.
Buying a Used GLE300d? What to Check
- Service history: Confirm every service was completed at or near the interval. Gaps in the log book on a car with complex diesel emissions systems are a significant risk.
- AIRMATIC suspension: Check each corner for sagging with the engine off on level ground. On a test drive, listen for compressor noise or clunking as ride height adjusts. A Mercedes-specific diagnostic scan for suspension fault codes is worthwhile.
- DPF and AdBlue status: A dealer scan can show DPF soot loading and any SCR fault codes. High soot loading on a car with no recent highway use may indicate a costly event is imminent.
- 12V battery condition: Ask for a battery conductance test. Any battery over three years old in a GLE300d deserves close scrutiny.
- Recall compliance: Confirm the 48V harness recall and transmission software recall have both been completed. A dealership can verify via VIN.
- MBUX: Test the screen, navigation, and Bluetooth during the test drive. Persistent reboots warrant caution.
- Finance check: Run a PPSR check before buying — high-value SUVs are commonly subject to outstanding finance or encumbrances. A full VIN check can also reveal write-off history.
The Verdict
The Mercedes-Benz GLE300d (W167) is one of the more accomplished large luxury SUVs sold in Australia in recent years. Well-maintained examples with full service history are capable of delivering genuine long-term reliability. The areas of highest risk for a used buyer are the AIRMATIC suspension (expensive once air struts and the compressor begin to fail), the AdBlue/SCR system (sensitive and costly when sensors or the dosing injector fail), and the 48V electrical components. Major dealer services typically run $700–$1,500, and specialist repairs easily exceed that. Verify recall compliance, insist on a full service record, and budget realistically for the running costs of a prestige diesel before committing.