300/350 3.5 V6 (M272 / M276)
2008–2015 · petrol · 3498cc · 306hp
Engine codes: M272, M276
Reliability, common problems and owner reviews for the Mercedes Benz GLK 300/350 3.5 V6 (M272 / M276). Check this before you buy used.
The petrol GLKs use the 3.5 V6 — the earlier M272 and later M276. The early M272 (pre-facelift) carries the known balance-shaft/idler-gear wear risk (timing-correlation fault, expensive engine-out repair), so verify history or prefer a facelift M276, which dropped that flaw. Both are smooth but thirsty in the SUV. Watch DI intake carbon (M276) and the usual ignition/cooling items. The diesels make far more sense for most buyers.
Same engine, other cars
This is the same physical engine (M272) sold under different names across brands. Reliability is broadly shared — cross-check these:
Known Issues
Early M272 balance-shaft/idler gear wears → timing-correlation fault; expensive engine-out fix.
Fix / Workaround: Check for correlation codes; verify history; prefer M276 facelift.
Repair cost: €1500–€3500
Typically appears after: 120,000 km
M276 DI intake carbon over time; both thirsty.
Fix / Workaround: Decarbon if rough; budget for fuel.
Repair cost: €200–€700
Year Cutoffs
Mileage Thresholds
After 150,000 km: M272 balance-shaft risk (early).
Pre-Purchase Checklist
- ☐Early M272: balance-shaft/correlation history
- ☐Prefer facelift M276
- ☐Thirsty — diesel is the sensible GLK
Frequently asked questions
Is the Mercedes Benz GLK 300/350 3.5 V6 (M272 / M276) reliable?
Maint. Sensitive — The petrol GLKs use the 3.5 V6 — the earlier M272 and later M276. The early M272 (pre-facelift) carries the known balance-shaft/idler-gear wear risk (timing-correlation fault, expensive engine-out repair), so verify history or prefer a facelift M276, which dropped that flaw. Both are smooth but thirsty in the SUV. Watch DI intake carbon (M276) and the usual ignition/cooling items. The diesels make far more sense for most buyers.
What are the common problems and reviews for the Mercedes Benz GLK 300/350 3.5 V6 (M272 / M276)?
The most commonly reported problems: Balance-shaft / idler-gear (early M272), Intake carbon (M276) / fuel use.
Is a used Mercedes Benz GLK 300/350 3.5 V6 (M272 / M276) worth buying?
Fine if serviced correctly — but it punishes neglect hard. History and the right consumables matter.