Mercedes-benz M-class (1998-2004)

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Which? Car review
Mercedes-Benz M-class (1998-2004)
Apr 1998 Class: 4x4s/SUVs
New price: - Used price: From £1,995
On sale:
Performance:
Ride comfort:
handling:
★★★
★★★
★★★★
Boot & Storage:
Safety:
★★★★★
★★★★
Reliability:
-
Total score:
-
Copes well with off-roading and towing.
Luxurious and spacious interior.
Strong safety features.
Crude road manners.
Very expensive parts and maintenance.
High fuel consumption - even diesels.
Recommended models
in the range
Which? Car Top Choice Model
ML270 CDI 5dr Tip Auto
New price: Used price: £2,975
Fastest Model
ML55 5dr Auto
New price: Used price: £3,275
6.8 secs
0-62mph:
Most Efficient Model
ML270 CDI Inspiration 5dr
New price: Used price: £3,525
Combined fuel economy:
30.1 mpg
Cheapest Model to buy new
New price:
Overview
Mercedes-Benz’s off-roader enjoyed a starring role in Jurassic Park. But is the original M-class
now a motoring dinosaur? Certainly the upmarket lustre it emanated at launch appears to have
dimmed in the eyes of used car buyers - it’s now in bargain basement territory. Maybe that’s
down to its very high running costs.
Get past these issues, though, and the American-built M-class has many virtues: the
strength to tow up to 3.5 tonnes, convincing off-road abilities and plenty of space inside for
passengers and luggage.
The original M-class shuffled off its mortal coil in 2004. It was replaced with a muchimproved second generation version, which continued till 2012. The Mercedes M-class competes in the full-size SUV class, up against the BMW X5, Range
Rover, Lexus RX, Volvo XC90 and VW Touareg. If you need to tow something heavy, there’s very little that can match an M-class.
Running costs can be astronomical. Avoid the over-engined ML500 and AMG55, and examples with manual transmission. The
ML270 CDI diesel automatic is the best choice. -
Cheapest Model to buy used
ML320 5dr Auto
Used price:
£1,995
Cheapest Model to Run (new)
New price: Running costs: (3 years/36,000 miles)
Owner’s View
This car is without doubt
the most comfortable
and safe vehicle I have
ever owned. The driving
position, seat ergonomics
and internal finish quality
are first class. The minor
irritating electrical
problems have been the
most disappointing things
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
On the road
How we test
The ML 320 CDI diesel automatic, as tested, is easily the best model in the range in terms
of day-to-day performance, smoothness and general running. The M-class is rather let down
by its crude chassis, which seems set up for American tastes rather than European ones: its
cornering is cumbersome and its ride quality can be jiggly. The M-class really comes into its
own on rough terrain, though. Performance
★★★
We tested the ML 270 CDI diesel, whose five-cylinder engine performs adequately, including
being able to tow up to 3,500kg. Automatic transmission is a much better option than manual
- it’s smooth and jolt-free, and ratios can also be selected manually. A push-button low-speed
transfer box is provided for off-road duty.
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Ride comfort
Acceleration (37-62mph)
7.9 secs
We use the sophisticated electronic timing
equipment to record standing-start and
in-gear acceleration, and repeat each test
several times.
Ride comfort
Rating
★★★
★★★
The M-class has a separate-chassis construction, which makes it feel a bit crude. While the
suspension damps high-speed bumps well, it’s not so great at low speed, and potholes really
catch it out. The body also rolls markedly when cornering.
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Performance
Rating
★★★
Ride comfort is assessed by our laboratory experts who have driven hundreds of
thousands of miles in a myriad of different
models.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
On the road continued...
How we test
Handling
★★★★
Handling
With its standard electronic stability control and permanent four-wheel drive, the M-class
corners safely enough, with good grip whatever the road conditions. It never feels very
connected to the road, however, with understeer transferring to oversteer in extreme
manoeuvres. The steering is very light and imprecise.
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Rating
★★★★
★★★★
Brakes
On-the-limit handling is explored well
away from public roads to ensure a fair
test. Our obstacle avoidance test is one of
the harshest tests in the industry..
Brakes
A stopping distance of 42.5m from 62mph is about what you’d expect for a large SUV. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Braking distance (62-0mph)
42.4m
Rating
★★★★
★★★★★
Refinement and noise
The M-class is relatively quiet, even at high speeds. It’s generally well built, but owners have
levelled a number of criticisms at it, particularly the quality of its electrical items. Some of the
cabin materials are a bit low-rent for a Mercedes, too. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Cruising noise
272dB
The Which? Car braking test measures
stopping distance from 62-0mph and is
repeated ten times in quick succession to
highlight any brake fade issues.
Refinement and noise
Rating
★★★★★
The Which? Car experts use a decibel
meter to record interior sound levels
at common UK motorway speeds, and
combine this with subjective assessments
to arrive at an overall score.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
On the road continued...
How we test
Cabin and controls
★★★★
Cabin and controls
The steering wheel is only height-adjustable, not reach-adjustable, but most drivers should be
able to achieve a comfortable driving position. The audio and climate control systems are well
sited and easy to operate. We’re not so keen on the positioning of some of the switchgear,
though, notably for the electric windows, mirrors and fog lamps. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Rating
★★★★
★★★★★
Visibility and parking
We penalise cars with difficult controls,
and we look for things like backlit light
switches and easy-to-use heating and
ventilation adjustments.
Visibility and parking
The tall seating position gives you a commanding all-round view of the road. Visibility generally
is good, but the view to the rear is impaired by the rear headrests, which can’t be pushed
down.
Although the steering is very light, the car’s cumbersome turning circle makes parking
awkward.
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Turning circle
11.9m
Rating
★★★★★
Visibility is a major issue for motorists
today, so each car gets a 360-degree
swivel view test to reproduce the driver’s
eye view and any obscured areas.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Comfort and practicality
How we test
The M-class is impressively spacious, both for passengers and luggage. Many cars were
ordered as seven-seaters with an extra third row of seats. Getting in and out
Getting in and out
★★★★
The tall bodywork makes getting in and out pretty easy. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Seat space and comfort
Rating
★★★★
★★★★★
Both front and rear, things are very spacious: even if you’re 2m tall, you’ll be able to feel
comfortable, and there’s plenty of shoulder width as well. The optional Family Pack adds an
extra pair of fold-away seats in a third row, but these are much more cramped. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
We take measurements all around the
driver and passenger’s door apertures
and note the height of the seat, door sills
and step down onto the car floor. The
best cars don’t require too much bending
or stretching to get in and out.
Seat space and comfort
Rating
★★★★★
We assess seat comfort subjectively,
using our road testers’ expert knowledge
and experience from thousands of different cars. And we measure the head-, legand elbowroom on offer in every seat, to
see how well the car caters for people of
all shapes and sizes.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Comfort and practicality continued...
How we test
Boot and storage
★★★★★
Boot and storage
At 510 litres, the luggage compartment is large for the class. With the asymmetrically-split rear
seats folded down, that increases to an impressive 950 litres (measured to the window line).
The very large tailgate opening, flat load floor and practical shape of the boot make for easy
stowage of bulky items. However, if you’re over 1.8m tall, you can all too easily bump your head
on the open tailgate. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Heating and ventilation
Boot space (seats up/down)
505 litres / 505 litres
Rating
★★★★★
★★★★★
Automatic climate control is standard on all M-classes, with separate zones for front and rear
passengers. It works well generally, but in cold weather it can take seemingly forever to warm
up - especially in the rear. Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Carmakers give official stats for boot
space, but our tests are more realistic. We
load the boot up with measuring blocks
only as far as the rear window line, so
that luggage is well secured and won’t
obscure rear visibility. We repeat the test
with the rear seats up, and folded down
(where possible).
Heating and ventilation
Rating
★★★★★
Feel sorry for the tester who has to warm
each car up from a frosty -10 degrees in
our climate chamber. Starting with a cold
engine, we measure how long it takes to
warm up the front and rear of the cabin.
Diesel cars usually take longer. We also
check the effectiveness of air conditioning, where fitted.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Running costs and depreciation
How we test
The M-class is potentially one of the most expensive cars on the road to keep going. Crippling
fuel consumption (whether petrol or diesel), very high maintenance costs and expensive
Mercedes parts all have a role to play. Insurance costs are high, too, ranging from group 38
(ML 320 CDI) up to group 50 (ML 55 AMG). Fuel consumption
Fuel consumption
We tested the ML 320 CDI automatic, which Mercedes claims should average 29.7mpg - we
achieved only 28.5. It gets worse if you opt for a petrol engine, with claimed averages ranging
from 21.7mpg (ML 320) down to just 19.1mpg (ML 55 AMG). Petrol (combined mpg, claimed)
19.1 mpg - 22.2 mpg
Diesel (combined mpg, claimed)
29.7 mpg - 30.1 mpg
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Urban (claimed/measured)
22.8 mpg/23.0 mpg
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Extra urban (claimed/measured)
35.3 mpg/35.3 mpg
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Motorway (measured)
28.2 mpg
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Combined (claimed/measured)
29.7 mpg/28.5 mpg
We test fuel economy under strict lab
conditions – using realistic test cycles – to
reveal the facts behind the figures. Our
figures rarely match manufacturer claims
as, unlike the official mpg test, we measure economy with both a hot and cold
engine, and on the motorway.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Running costs and depreciation continued...
How we test
Emissions
Emissions
Every model in the M-class range emits a lot of carbon dioxide: from 248g/km to 354g/km. Its
saving grace is that this generation predates the March 2006 cut-off point for the highest VED
road tax banding. Petrol (CO2, claimed)
305g per km - 354g per km
Diesel (CO2, claimed)
248g per km - 250g per km
Model tested
diesel 2.7 (163bhp) auto 5dr (2003)
Emissions (claimed/measured)
250g per km/-
While testing fuel economy, we also
collect exhaust gases to enable us to
measure the amount of carbon dioxide
(CO2) emitted. We also check whether
particulate filters are effective at removing
sooty emissions from diesel engines.
Safety
Safety and security
For its day, the M-Class had state-of-the-art safety standards. In addition to front and front-side
airbags, it had end-to-end window bags - and rear side airbags were optional. Stability control
is standard on all examples. However, the headrests fore and aft are only big enough to
protect occupants up to 1.75m tall. The M-class’s credentials as family transport are dented somewhat by the fact that
fitting child seats in the rear using the car’s seat belts is pretty awkward, and not all types of
child restraint system will fit. It’s preferable to use Isofix if possible. Note that only an official
Mercedes child safety seat can be fitted to the front passenger seat. Euro NCAP score
★★★★
The M-class scored four out of five stars in the Euro NCAP adult occupant crash test, but only
one star out of four in the pedestrian test.
Adult occupant
Child protection
Pedestrian protection
We rate cars for safety using Euro NCAP
crash test scores (where available),
alongside our own comprehensive safety
checklist. Uniquely, we also feed in results
from our accident avoidance test – after
all, it’s far better to steer around a crash
than rely on the airbags...
Security
★★★★
★
Which? safety rating
★★★★
Active (crash avoidance)
Passive (crash safety)
Child
Pedestrian
-
Security
This is a difficult car to steal, scoring a maximum five stars for theft of the vehicle. However, its
‘theft from’ score was less impressive - three stars.
Theft of car: Theft from car:
★★★★★
★★★
Security scores come from the security
experts at Thatcham, who break into
hundreds of cars each year. Most modern
cars are very difficult to drive away, but
are still too easy to steal from.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Which? Car Survey results
About our survey
The Which? Car Survey is the UK’s most robust reliability and owner satisfaction survey. In
2015, drivers told us about 58,000 cars, covering more than 484 million miles in the previous
12 months (that’s equivalent to driving to the moon and back a hundred times). This unique
feedback allows us to rate satisfaction and reliability for hundreds of new and used cars.
Note: Star ratings below are from 1-5 (1 is very poor and 5 is very good). Percentages
shown under ‘Most common faults’ indicate the proportion of owners reporting each problem
in the past 12 months.
Brand
Sample size: 2,292 people
Mercedes-Benz ratings
Overall owner satisfaction for this brand
Brand reliability
Dealer Sales Service
Dealer Servicing & repair
Model: Mercedes-Benz M-class (1998-2004)
83%
Sample size: - people
Overall owner satisfaction for this range
-
-
-
-
-
-
-
-
Everyone who takes part in the Which?
Car survey tells us about their car and
the dealers who sell and service it. We
analyse this feedback across all cars to
give top-level satisfaction ratings for each
brand, including the brand’s reliability
record over the last eight years. All star
ratings are out of five.
Model ownership ratings
★★★★
★★★★
Ownership ratings
-
Brand ratings
These show how owners score this car
in 12 different areas, from performance to
heating. Owners’ ratings are subjective –
so may differ from Which? Car test scores
– but they give a good idea of what the
car is like to live with. Where relevant, cars
are scored against other cars in the same
class (e.g. for space).
-
Owner’s View
My Mercedes looks good,
drives well and does
everything that I ask of it
from carrying heavy loads
to travelling long journeys
(South of France in a day).
Used to be a Landy man but
not any more! The ride can
be a bit springy, but that
Owner’s View
It has been a joy. It will be
10 years in Septemeber
with me. All major problems
happened while under
warranty. Since the end of
the warranty, it has been
good.
Which? Car review
Mercedes-Benz M-class (1998-2004)
4x4s/SUVs
Which? Car Survey results continued...
About our survey
Reliability ratings
Reliability ratings
-
Overall Reliability
Petrol cars
Reliability
Breakdowns
Average annual repair cost
Diesel cars
Reliability
Breakdowns
Average annual repair cost
All cars
Reliability
Breakdowns
Average annual repair cost
Up to 3 years old
4-8 years old
-
-
-
-
-
-
-
-
-
-
We split reliability into breakdowns (including failure to start), faults (where parts
need replacing) and problems (minor issues e.g. squeaks and loose trim). Where
the car has been on sale for some time,
and we have numerous survey responses
from owners, we also split scores by the
age of car and fuel type. Star ratings are
out of five – the more stars, the more reliable the car.
Most common faults
Breakdowns: Percentage of cars suffering a breakdown in last 12 months
Average annual repair cost: Average annual cost of repairs (not servicing), in past 12
months
Most common faults
Up to 3 years old
-
-
-
4-8 years old
-
-
-
-
-
-
-
-
-
Failure rate: The proportion of owners reporting this problem in the last year
Want to know what’s most likely to go
wrong as the car gets older? These are
the five most common faults reported by
owners, grouped by age into new, recent
and older cars. A score of 40% means
four out of 10 owners reported problems
with that part of the car over the previous
12 months. Engine electrics and non-engine electrics (e.g. windows, stereo) cause
more headaches than mechanical parts in
most modern cars.