20 BMWcar
BUYING GUIDE
after just 40,000. Low-mileage, stop-start
vehicles are likely to suffer more with
carbon build-up, as are those run on poor
quality fuels.
“In terms of gearbox choice, there are
arguments in favour of both the manual
and the automatic options. The former
offers brilliant fuel economy and more
driving satisfaction, although turbo lag
between the gear changes is less of a plus
point. However, the automatic was the
more popular choice when the car was
new; I think about 70% of 330ds were
specified this way from the factory.”
SMOOTH AUTOS
“This model was fitted with the ZF 6HP
automatic transmission,” Andy continued,
“which is a really good gearbox. However,
there is a price to be paid in terms of
fuel economy, although the drop-off isn’t
huge; nothing like it used to be in previous
generations.
“The manual gearboxes do suffer with
clutch and flywheel issues because of the
sheer amount of torque from the diesel
engine. Wear rates will be increased on cars
that have been used for towing, so bear
this in mind if you’re looking at a car fitted
with a tow bar. Another factor influencing
the wear is the amount of vibration from
the diesel engine, which is inherently much
greater than with a petrol-powered unit.
“The tell-tale signs of this sort of failure
can be a chatter on start-up, the gear lever
jumping around and even the sensation that
the engine is suffering with a misfire when
under load. In bad cases, the flywheel can
start to break up, which isn’t good news.
When testing a prospective purchase, notice
how the clutch feels as you operate the
pedal. If you detect any sort of ‘lump’ in the
travel, or excessive weight to the pedal at
either the top or the bottom of the travel,
then beware. Also, of course, if the biting
point is very close to the top of the travel,
then the clutch is likely to be on its last legs.”WEAR AND TEAR
Searching online for cars for sale, it’s
usually the case that, like-for-like, the 330d
models will have covered greater mileages
than the 330is. This, of course, places a
greater strain on the running gear, so it’s
important to be aware of suspension and
brake condition. “It’s often the case that the
suspension on a 330d will be pretty much
toast after about 130,000 miles,” Andy
explained, “with new shock absorbers and
top mounts being required all round. So, if
none of that has been done on a car you’re
considering, then you should factor in the
cost of that work.
“Suspension bushes tend to last pretty
well, though, with just about the only issue
concerning the upper suspension arm link
on both sides, at the rear of the car. When
worn, these bushes will allow too much
negative camber and free play in the rear
wheels. At the front, wear will affect the
brake reaction arms, which lead a hard life
due to the weight of the diesel engine.”
The good news, though, is that
suspension parts for the E90 aren’t
expensive to buy. Being a run-of-the-mill 3
Series saloon, nothing should be shockingly
expensive and stock availability will be
good. The most expensive bits will be the
diesel injectors, turbocharger and flywheels
which, if needed, will cost £560, £1,
and £1,124, respectively (plus fitting).
The final point to mention with regard to
the 330d is the dreaded, diesel particulate
filter (DPF), which can be a cause of
potentially expensive trouble. “To work
effectively,” Andy said, “the DPF needsto be at its operating temperature, which
requires a coolant temperature of at least
75°C, and an exhaust temperature in
excess of 400°C.”FILTER FOUL-UPS
“Diesel-engined cars that are only being
used for short, stop/start journeys may
struggle to reach these temperatures
(especially if there are issues with the
thermostat), which is bad news for the DPF
which can become clogged with carbon.
“More normally, though, DPF failure isRide quality isn’t helped by the
standard-fit runflats, which is
why many owners switch to more
compliant and less expensive
conventional tyres.The M57, diesel six offers lashings of torque and great
economy, even when paired with an auto transmission.
Right: The 330i’s naturally-aspirated straight-six offers a
lovely, smooth power delivery, but has to be worked harder
than the M57 in the 330d.