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Mercedes Benz GLC Class Engine ReplacementCompare Prices & Save
Get quotes today from trusted UK Mercedes Benz GLC Class engine specialists. Compare prices on reconditioned, rebuilt and used engines - supply & fit available nationwide.
GLC Class Diesel Engines - from £1,800 to £5,500
-> Rebuilt units from £2,450 · Common codes: OM654, OM651, OM656
GLC Class Petrol Engines - from £1,600 to £4,800
-> Rebuilt units from £1,950 · Common codes: M274, M264, M260
GLC Class AMG Engines - from £4,500 to £12,000
-> Rebuilt units from £5,200 · Common codes: M276, M177, M139
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3 Simple Stepsto Finding the Best Mercedes Benz GLC Class Replacement Engine
Get Instant Quotes from Mercedes - Benz Engine Specialists Across the UK - 100% free, no obligation. Most replacements completed within 3-5 days.
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Live UK Engine Market Data
What Are UK Drivers Paying for Mercedes Benz GLC Class Engine Replacement?
UK rebuilt engine costs for Mercedes GLC Class variants below show documented failure causes, engine codes and specifications based on current market data.
Average Market Prices
- Mercedes Benz GLC Class (X253) GLC 63 AMG2018-2022£7,000-£12,000Cylinder bore scoringM177Petrol 4.0L
- Mercedes Benz GLC Class (X254) GLC 2002022-2025£2,500-£4,500Oil consumptionM264MHEV Petrol 2.0L
- Mercedes Benz GLC Class (X254) GLC 220d2022-2025£2,800-£5,000DPF regeneration faultOM654MHEV Diesel 2.0L
- Mercedes Benz GLC Class (X254) GLC 300e2023-2025£4,000-£7,000Electric motor bearingM254PHEV Petrol 2.0L
- Mercedes Benz GLC Class (X253) GLC 220d2015-2019£2,200-£3,800EGR cooler failureOM651Diesel 2.1L
- Mercedes Benz GLC Class (X253) GLC 220d2019-2022£2,400-£4,200AdBlue injector faultOM654Diesel 2.0L
- Mercedes Benz GLC Class (X253) GLC 250d2015-2019£2,300-£3,900Swirl flap failureOM651Diesel 2.1L
- Mercedes Benz GLC Class (X253) GLC 300d2019-2022£2,800-£4,800NOx sensor failureOM654Diesel 2.0L
- Mercedes Benz GLC Class (X253) GLC 350d2015-2019£3,000-£5,200Oil cooler seal leakOM642Diesel 3.0L
- Mercedes Benz GLC Class (X253) GLC 2002015-2019£2,000-£3,500Timing chain wearM274Petrol 2.0L
- Mercedes Benz GLC Class (X253) GLC 3002019-2022£2,200-£4,000Cylinder head failureM264Petrol 2.0L
- Mercedes Benz GLC Class (X253) GLC 350e2016-2022£3,500-£6,000Hybrid battery failureM274Hybrid 2.0L
- Mercedes Benz GLC Class (X253) GLC 43 AMG2016-2019£4,500-£7,500Camshaft adjuster wearM276Petrol 3.0L
Last updated: 22 May, 14:59
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Models We Cover
Mercedes Benz GLC Class Engine ReplacementAll Variants Covered
From the efficient GLC200 to the ferocious GLC63 AMG, our trusted UK Mercedes Benz GLC Class engine specialists help you compare rebuilt, reconditioned and used engine prices. Typical price range for a rebuilt unit with 12-month warranty is £1,950-£5,500 - supply & fit available nationwide.
Core Diesel Range
Specs170hp
Years2015-2019
Rebuilt£2,200-£3,800
Specs170hp
Years2015-2019
Rebuilt£2,200-£3,800
Core Petrol Range
Performance & AMG Range
Variant Directory
All Mercedes Benz GLC Class Variants - Engine Replacement Coverage
Diesel Variants
GLC 200dGLC 220dGLC 220d 4MATICGLC 250dGLC 250d 4MATICGLC 300dGLC 300d 4MATICGLC 350d 4MATICGLC 400d 4MATIC
Petrol Variants
GLC 200GLC 200 4MATICGLC 250GLC 250 4MATICGLC 300GLC 300 4MATICGLC 300 4MATIC CoupePerformance Variants (AMG)GLC 43 4MATICGLC 43 4MATIC CoupeGLC 63 4MATIC+GLC 63 S 4MATIC+GLC 63 S 4MATIC+ CoupeHybrid & Electrified VariantsGLC 300eGLC 300e 4MATICGLC 350eGLC 350e 4MATICGLC 400e 4MATICBody Style Variants (All trims available as Coupe where indicated above)GLC Class SUV (X253)GLC Class Coupe (C253)GLC Class SUV (X254)GLC Class Coupe (C254)Not sure which variant your Mercedes Benz GLC Class is? Enter your registration number above - we'll identify the exact sub‑model, engine code and compatible replacement options instantly.
Engine Codes
Mercedes Benz GLC Class Engine CodesFull Technical Specifications & Replacement Guide
Every engine code fitted to the Mercedes Benz GLC Class across all generations (X253, C253, X254), with technical specs, compatible variants and trims, known failure points, and average rebuilt prices from UK specialists. Select any engine code to compare quotes.
Diesel Engines
Extracted from detailed diesel engine families across Mercedes Benz GLC Class variants.
Petrol Engines
Extracted from detailed petrol and performance engine families across Mercedes Benz GLC Class variants.
Hybrid / Electrified Engines
Extracted from electrified powertrains and hybrid engine families used in Mercedes Benz GLC Class variants.
Can't find your engine code?
Common Problems
Mercedes Benz GLC Class Engine Problems
What It Costs to Fix & When Replacement Makes Sense
The Mercedes GLC Class (X253, C253, X254) is a refined premium SUV, but its OM654 diesel and M274/M264 petrol engines have well-documented weak points that drive replacement demand. Timing chain stretch on earlier four-cylinders, EGR cooler cracking on the OM654, and camshaft adjuster failure on the V6 M276 are the most searched failure patterns. Every rebuilt engine supplied through EngineMarket includes upgraded internal components designed to address the original failure point - plus a minimum 12-month unlimited mileage warranty. Below, we break down the costs and decision points for the GLC's most common engine failures.
Every rebuilt engine includes a minimum 12-month unlimited mileage warranty.
1. Mercedes GLC OM654 EGR Cooler Cracking
The Most Searched Diesel Failure
Affected Models
GLC 220d, GLC 300d (2019-present, OM654 engine)
Typical Failure Mileage
40,000 - 80,000 miles
Root Cause
The original EGR cooler (part A6540940101) suffers thermal stress fractures, allowing coolant to enter the exhaust system, triggering low coolant warnings, misfires, and eventually engine overheating.
Repair Options & Estimated Costs (UK ranges)
| Repair Tier | Dealer Price | Specialist Price | What It Involves | Longevity / Suitability |
|---|---|---|---|---|
EGR Cooler Replacement - Cooler-only swap Minor | £1,100 - £1,600 | £700 - £1,100 | Replace failed EGR cooler with revised OEM unit, drain and refill coolant, clear fault codes | 3-5 years (revised cooler more durable but same design) |
Full Replacement - Rebuilt engine with upgraded cooler Best Value | £6,500 - £9,000 | £4,200 - £5,800 | Supply & fit of bench-tested OM654 rebuilt engine with reinforced EGR cooler upgrade (brazed A6540940001), new gaskets, timing components | 100k+ miles with warranty backing |
Our Recommendation
Best next step for mercedes glc om654 egr cooler cracking
If caught early with no overheating damage, replace just the EGR cooler. However, many cases present after coolant loss has caused cylinder head damage. On a GLC worth £18,000-£25,000, the full engine replacement with upgraded cooler is the safer long-term investment. Specialist pricing beats dealer by 30-40%.
Don't Let Engine Failure Write Off Your Mercedes GLC Class
Whether you're facing OM654 EGR cooler failure, M274 timing chain rattle, or M276 camshaft adjuster issues on your AMG, EngineMarket makes it simple to compare quotes from trusted UK Mercedes GLC Class specialists. Every rebuilt engine in our network carries upgraded components addressing the original design weakness - plus a minimum 12-month unlimited mileage warranty with nationwide delivery and supply & fit options. Don't pay main dealer premiums. Compare prices from independent Mercedes specialists who know these engines inside out.
Compare Mercedes Benz GLC Class Engine Replacement Prices Now →Mercedes Benz GLC Class Engine Problems
What It Costs to Fix & When Replacement Makes Sense
The Mercedes GLC Class (X253, C253, X254) is a refined premium SUV, but its OM654 diesel and M274/M264 petrol engines have well-documented weak points that drive replacement demand. Timing chain stretch on earlier four-cylinders, EGR cooler cracking on the OM654, and camshaft adjuster failure on the V6 M276 are the most searched failure patterns. Every rebuilt engine supplied through EngineMarket includes upgraded internal components designed to address the original failure point - plus a minimum 12-month unlimited mileage warranty. Below, we break down the costs and decision points for the GLC's most common engine failures.
Affected Models
GLC 220d, GLC 300d (2019-present, OM654 engine)
Typical Failure Mileage
40,000 - 80,000 miles
Root Cause
The original EGR cooler (part A6540940101) suffers thermal stress fractures, allowing coolant to enter the exhaust system, triggering low coolant warnings, misfires, and eventually engine overheating.
EGR Cooler Replacement - Cooler-only swap
Dealer
£1,100 - £1,600
Specialist
£700 - £1,100
Replace failed EGR cooler with revised OEM unit, drain and refill coolant, clear fault codes
3-5 years (revised cooler more durable but same design)
Full Replacement - Rebuilt engine with upgraded cooler
Dealer
£6,500 - £9,000
Specialist
£4,200 - £5,800
Supply & fit of bench-tested OM654 rebuilt engine with reinforced EGR cooler upgrade (brazed A6540940001), new gaskets, timing components
100k+ miles with warranty backing
Our Recommendation
Best next step for mercedes glc om654 egr cooler cracking
If caught early with no overheating damage, replace just the EGR cooler. However, many cases present after coolant loss has caused cylinder head damage. On a GLC worth £18,000-£25,000, the full engine replacement with upgraded cooler is the safer long-term investment. Specialist pricing beats dealer by 30-40%.
Don't Let Engine Failure Write Off Your Mercedes GLC Class
Whether you're facing OM654 EGR cooler failure, M274 timing chain rattle, or M276 camshaft adjuster issues on your AMG, EngineMarket makes it simple to compare quotes from trusted UK Mercedes GLC Class specialists. Every rebuilt engine in our network carries upgraded components addressing the original design weakness - plus a minimum 12-month unlimited mileage warranty with nationwide delivery and supply & fit options. Don't pay main dealer premiums. Compare prices from independent Mercedes specialists who know these engines inside out.
Compare Mercedes Benz GLC Class Engine Replacement Prices Now →Disclaimer: All prices are indicative UK market ranges based on historical quote data and repair requests from our network of engine specialists. Dealer pricing is estimated based on published main dealer labour rates (£150-£250/hour) and genuine OEM parts pricing. Specialist pricing reflects actual quote data from EngineMarket's UK network. Actual costs vary depending on damage severity, vehicle condition, variant, and workshop location within the UK. Use our free comparison tool to get tailored quotes for your specific Mercedes Benz GLC Class and engine code. Every engine supplied through EngineMarket carries a minimum 12-month unlimited mileage warranty - always confirm exact terms with your chosen supplier.
12-Month Warranty
Upgraded Components
Nationwide UK Delivery
Save vs Main Dealer Price
Replacement Engine Options
Mercedes Benz GLC Class Engine TypesOptions, Costs & What to Expect
Every engine type for the Mercedes GLC Class (X253, C253, X254) is available through our UK network, with typical price ranges varying by variant, engine code and your budget.
All engine types include a minimum 12-month unlimited mileage warranty when sourced through EngineMarket. Prices are typical UK market ranges based on historical quote data from our network and depend on exact engine code, variant, mileage and supplier. Use our free comparison tool above - enter your registration to get tailored quotes for your specific Mercedes Benz GLC Class within hours.
Engine Sizes
Mercedes Benz GLC Class Engines by SizeFind the Right Displacement for Your Variant
Every displacement fitted to the GLC Class across X253, C253 and X254 generations is listed below, with compatible engine codes, years and common failure notes for each.
Mercedes Benz GLC Class Diesel Engine Sizes
The 2.0-litre diesel range forms the backbone of GLC diesel sales in the UK, spanning both the older OM651 (2015-2019) and the newer OM654 (2019-present) engines. The OM651 delivered strong torque and respectable economy, while the OM654 introduced stepped bowl combustion and lower friction for Euro 6d compliance. The OM654's EGR cooler cracking has become the most searched diesel failure pattern for this model.
| Engine Code(s) | OM651 (2015-2019), OM654 (2019-present) |
| Compatible Models (UK) | GLC 220d (2015-present), GLC 250d (2015-2019), GLC 300d (2019-present), GLC 200d |
| Production Years | 2019-2022 |
Common Failure Points
Watch for these known weak points
OM654 EGR cooler cracking, AdBlue injector clogging; OM651 swirl flap actuator failure, timing chain stretch
Not sure which engine size your Mercedes Benz GLC Class needs? Enter your registration number above - we'll identify the exact displacement, engine code and compatible replacement options instantly. All engines supplied through EngineMarket include a minimum 12-month unlimited mileage warranty from UK Mercedes Benz GLC Class specialists.
Mercedes Benz GLC Class Engines Fuel Type
Mercedes Benz GLC Class Engines by Fuel Type
Choose your Mercedes Benz GLC Class engine by fuel type to compare realistic replacement prices, known issues, and compatible UK supply options - from the efficient GLC 220d to the ferocious GLC 63 AMG.
Mercedes Benz GLC Class Diesel Engines
Mercedes Benz GLC Class Diesel Engines
Diesel powered the majority of GLC sales across the X253 (2015-2022) and X254 (2022-present) generations, with the OM651 and OM654 four-cylinders dominating replacement enquiries - particularly the OM654's EGR cooler failures.
Common Engine Families
OM651 - 2.1L four-cylinder (2015-2019 GLC 220d, 250d), known for swirl flap and injector issues
OM654 - 2.0L four-cylinder (2019-present GLC 220d, 300d), EGR cooler cracking is the most searched failure
OM642 - 3.0L V6 (2015-2019 GLC 350d), oil cooler seal leaks in the engine 'V' drive replacement decisions
Found In
X253 GLC Class SUV / C253 Coupe (2015-2022) - OM651, OM654, OM642
X254 GLC Class SUV / C254 Coupe (2022-present) - OM654 only
Known For
Strong motorway economy - 50+ mpg on OM654-equipped 220d models
OM654 EGR cooler cracking between 40k-80k miles - the dominant replacement driver
OM651 timing chain stretch and swirl flap actuator failure on higher-mileage units
OM642 V6 oil leaks that often exceed vehicle value to repair properly
Typical Models (UK)
GLC 220d
GLC 250d
GLC 300d
GLC 350d
Not sure which fuel type your Mercedes Benz GLC Class has? Enter your registration number above to instantly identify your engine code, fuel system and compatible replacement options - all backed by a minimum 12-month unlimited mileage warranty from UK Mercedes Benz GLC Class specialists.
Engine Years
Mercedes Benz GLC Class Engines by YearWhat Was Fitted & When
This technical timeline covers all major engine changes across the GLC Class production run (2015 to present), helping owners identify their exact powerplant and compare rebuilt engine prices from UK specialists.
2015-2019 - X253/C253 First Generation Launch
Major Platform Change
The GLC replaced the GLK in 2015, debuting on Mercedes' MRA platform with OM651 diesel and M274 petrol four-cylinders.
Key Changes
New X253 (SUV) and C253 (Coupe) body styles launched
9G-Tronic automatic transmission introduced across all variants
4MATIC all-wheel drive optional or standard depending on variant
Early build M274 engines subject to timing chain tensioner recall
Known For
Strong residual values and premium SUV refinement
M274 timing chain tensioner wear - cold start rattle from 60k miles
OM651 swirl flap actuator failures and injector carbon build-up
OM642 oil cooler seal leaks in the V6 engine 'V' - labour-intensive repair
Main Engines
OM651 - 2.1L diesel (GLC 220d, 250d)
M274 - 2.0L petrol (GLC 200, 250, 300)
OM642 - 3.0L V6 diesel (GLC 350d)
Popular Models
GLC 220d
GLC 250d
GLC 250
GLC 350d
Engine Codes Covered
OM651M274OM642
Common Replacement Enquiries
GLC 220d engine replacement
OM651 swirl flap failure
M274 timing chain rattle
GLC 350d oil leak repair
Get quotes for 2015-2019 Mercedes GLC Class replacement engines
2015-2019 - X253/C253 First Generation Launch
Major Platform Change
The GLC replaced the GLK in 2015, debuting on Mercedes' MRA platform with OM651 diesel and M274 petrol four-cylinders.
Key Changes
New X253 (SUV) and C253 (Coupe) body styles launched
9G-Tronic automatic transmission introduced across all variants
4MATIC all-wheel drive optional or standard depending on variant
Early build M274 engines subject to timing chain tensioner recall
Known For
Strong residual values and premium SUV refinement
M274 timing chain tensioner wear - cold start rattle from 60k miles
OM651 swirl flap actuator failures and injector carbon build-up
OM642 oil cooler seal leaks in the V6 engine 'V' - labour-intensive repair
Main Engines
OM651 - 2.1L diesel (GLC 220d, 250d)
M274 - 2.0L petrol (GLC 200, 250, 300)
OM642 - 3.0L V6 diesel (GLC 350d)
Engine Codes Covered
OM651M274OM642
Popular Models
GLC 220d
GLC 250d
GLC 250
GLC 350d
Common Replacement Enquiries
GLC 220d engine replacement
OM651 swirl flap failure
M274 timing chain rattle
GLC 350d oil leak repair
Get quotes for 2015-2019 Mercedes GLC Class replacement engines
Year Finder
Not sure which year your Mercedes Benz GLC Class was built?
Not sure which year your Mercedes Benz GLC Class was built? Enter your registration number and we'll identify the exact engine, model year, and compatible replacement options instantly - all backed by a minimum 12-month warranty from UK Mercedes Benz GLC Class specialists.
FAQ
Mercedes Benz GLC Class Engine ReplacementFrequently Asked Questions
Question 1
How much does a Mercedes GLC engine replacement cost in the UK?
A rebuilt GLC engine typically costs £2,400-£4,800 for the common 220d diesel, £2,200-£4,000 for the 300 petrol, and £7,000-£14,000 for the 63 AMG V8. Supply only - fitting adds £600-£1,200.
Key points
- • GLC 220d (OM654): rebuilt unit £2,400-£4,200; used engine from £1,500
- • GLC 300 (M264): rebuilt unit £2,500-£4,500; used engine from £1,800
- • GLC 43 AMG (M276): rebuilt unit £4,500-£8,000; specialist fit only
- • GLC 63 AMG (M177): rebuilt unit £7,000-£14,000; V8 specialist required
- • Price depends on engine code, year, mileage, and supplier warranty length
Question 2
Is the Mercedes GLC 220d engine reliable? What are the common problems?
The 220d's OM654 engine is fundamentally strong, but EGR cooler cracking between 40k-80k miles is the dominant failure - often requiring full engine replacement if coolant loss causes overheating.
Key points
- • OM654 EGR cooler (part A6540940101) fractures from thermal stress - most searched GLC diesel fault
- • AdBlue injector nozzle clogging (A0010780108) triggers countdown warnings
- • NOx sensor failure causes permanent emissions lights and failed MOT
- • OM651 in pre-2019 220ds suffers swirl flap actuator failure and timing chain stretch
- • Well-maintained OM654 diesels regularly exceed 200,000 miles despite these issues
Question 3
Which Mercedes GLC engine is most reliable - petrol or diesel?
The OM654 diesel (2019-onwards) delivers the best long-term reliability at high mileage. For petrol buyers, the M264 has more complex 48V hybrid components to fail, while the older M274 suffers timing chain tensioner wear.
Key points
- • GLC 250d with OM651 is considered "virtually indestructible" when maintained
- • GLC 300 with M264 offers good reliability but BSG (48V starter-generator) can fail
- • GLC 220d OM654 has one known weak point (EGR cooler) but otherwise very robust
- • M274 petrol engines pre-2017 have higher timing chain failure rates
- • Second-gen X254 (2022+) mild hybrids too new for long-term reliability data
Question 4
What are the signs of timing chain failure on a Mercedes GLC?
A 1-3 second rattling noise on cold start is the classic warning - most common on M274 petrol engines (GLC 200/250/300, 2015-2019). Ignoring it risks engine seizure and £5,000+ repair bills.
Key points
- • Cold start rattle that disappears after oil pressure builds - earliest warning sign
- • Check engine light with cam/crank correlation codes (P0016/P0017)
- • Metallic swarf in engine oil indicates chain guides wearing away
- • Rough idle or misfire means timing has already drifted
- • Preventative tensioner replacement costs £300-500 - full chain kit £1,200-1,700
Question 5
How long do Mercedes GLC engines last?
Properly maintained GLC diesel engines routinely reach 250,000-300,000 miles (400,000-500,000 km) before major work. Petrol engines typically need significant attention between 120,000-180,000 miles .
Key points
- • OM651 and OM654 diesels: 250,000+ miles with regular servicing
- • M274/M264 petrols: 150,000-200,000 miles before major repairs likely
- • OM654 EGR cooler typically fails once - after replacement, engine continues strongly
- • Service interval is 10,000 miles or 12 months - use Mercedes-spec oil only
- • AMG V8 engines (M276/M177) require more frequent maintenance - 120,000-150,000 miles typical
Question 6
Is it worth replacing the engine in my Mercedes GLC?
Yes, if the GLC is otherwise in good condition with no rust or major electrical faults. A rebuilt OM654 or M264 engine costs £2,500-£4,500 - far less than replacing a £18,000-£35,000 vehicle.
Key points
- • GLC values remain strong - X253 (2015-2022) still worth £15,000-£30,000+
- • Rebuilt engine with upgraded components (EGR cooler, timing chain tensioner) fixes original weak points
- • Supply & fit typically £3,000-£6,000 depending on engine code
- • New engine includes 12-month unlimited mileage warranty - peace of mind
- • Only consider scrapping if body corrosion, transmission failure, or structural damage present
Question 7
What engine oil does my Mercedes GLC need and how often?
Mercedes-Benz specifies 229.51 or 229.52 low-SAPS oil (5W-30 or 0W-20 depending on year). Change every 10,000 miles or 12 months - stretched intervals cause timing chain wear and turbo failure .
Key points
- • OM654 diesel: MB 229.52 0W-20 or 5W-30 - low-ash formula protects DPF
- • M274/M264 petrol: MB 229.5 5W-30 or 0W-40 - high-spec synthetic only
- • Never use non-approved oil - destroys timing chain tensioners and hydraulic lifters
- • OM642 V6 diesel requires 8.5 litres of 5W-30 low-SAPS oil
- • Late oil changes are the #1 cause of preventable engine failure on all GLC engines
Question 8
What causes AdBlue failure on Mercedes GLC diesels?
AdBlue crystallises inside the injector nozzle (A0010780108), blocking flow and triggering countdown starters - OM654 engines (2019+) are most affected. NOx sensor failure is the second most common emissions fault.
Key points
- • Crystallisation blocks the injector - ultrasonic cleaning helps but replacement often needed
- • Countdown starts at 16 starts remaining - ignore and car won't restart
- • NOx sensors fail due to internal heating element degradation
- • Repair cost: injector £280-450, sensor replacement £350-600 each (replace both)
- • Using poor-quality AdBlue or letting tank run dry accelerates injector failure
Question 9
Are second-generation X254 GLC engines (2022+) reliable?
Too early for definitive long-term data, but early owner feedback suggests OM654M diesels and M254 mild hybrids are proving more reliable than first-gen facelift engines. No major systematic failures reported.
Key points
- • OM654M diesel includes revised EGR cooler - fewer cracking reports so far
- • Integrated starter-generator (ISG) replaces problematic belt-driven BSG from M264
- • GLC 300e PHEV offers 80-mile electric range - battery health unknown long-term
- • GLC 43 now uses M139l four-cylinder - reliability unproven, early AMG feedback mixed
- • First major repairs expected after 100,000-150,000km - watch this space
Question 10
Should I buy a GLC 300e plug-in hybrid or stick with diesel?
Choose the 300e PHEV if you have home charging and mostly do sub-50 mile daily trips - 5% BIK tax saves company car drivers £3,000 annually over the 220d. Choose diesel for high-mileage motorway use where battery range won't be utilised .
Key points
- • GLC 300e offers 55-80 miles electric range - covers most daily commutes
- • 5% Benefit-in-Kind (BIK) tax vs 37% for diesel - huge company car saving
- • Petrol PHEV cheaper to buy than diesel 300de - £3,000/year lower tax
- • Real-world economy on long journeys: diesel 45-50mpg, PHEV 35-40mpg (battery depleted)
- • Diesel better for towing - PHEV's extra battery weight reduces payload
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