|
Getting EDGEucated:
The "75k Mile List"
The E32 7- Series (1988-1994) Edition
After
years of working on BMW's, we have begun to see common problems and
maintenance concerns that need to be addressed on nearly every
middle-aged BMW. Like all BMWs, 7's have certain
areas that need to be inspected regularly, and prospective owners
should always have a pre-purchase inspection done to verify the
condition of these items.
In this list, you will find items that should have been replaced or at
least inspected by 75k-100k miles. Some are model specific, and will be
noted as such.
If you suspect you may have some of these issues, or just want us to
take a look for your peace of mind, call us at 925.479.0797 to schedule an appointment!
Areas of Concern:
Thrust Arm Bushing Failure
Common
symptoms for torn or cracked thrust arm bushings are undesired front
toe changes during cornering, vague and rubbery feel in the steering,
and vibration experienced while braking at freeway speeds. Extreme
examples will also produce a clunking sound. EVERY 5 and 7 series car
we have ever seen needs these replaced by 75k.
Tie Rod Wear
5
and 7 series cars share the same basic front steering components,
consisting of a tie rod end attached to each end of the center tie rod.
All three components contain ball joints and any one of them may cause
steering shimmy. If any of the ball joint boots is cracked (you'll see
grease coming out) then expect that component to need replacement. All
components should also be checked for excessive play, and replaced if
out of BMW spec.
Worn or Blown Shocks and Struts
Factory BMW
shocks work great for about 30k. By 60k they are completely shot.
Most folks who have been driving their cars since new hardly notice
the deterioration as it is gradual. Symptoms include:Diving under
braking and acceleration, excessive lean and suspension compression
during cornering. Bouncy and uncomfortable ride. Shocks and struts may
visibly leak shock oil.
EDGE
generally recommends replacing the factory units with quality shocks
from Koni whenever possible. When replacing shocks and struts, keep
in mind it is a great time to install lowering springs or freshen up
other areas of the suspension. You will be amazed at the difference a
good set of shocks can make in both comfort and performance!
Worn or Failed Swaybar Endlinks
Worn swaybar
endlinks can compromise handling. A worn swaybar can sound like a
metallic clicking noise. There is no critical danger in a failed
swaybar endlink, but the handling of the car is severely compromised.
Torn Subframe and Subframe Bushings
Torn or Worn
subframe bushings may lead to subframe failure. Common symptoms of
subframe failure are erratic handling and unidentified clunks, squeeks
and bangs from the rear of the car. Early detection of a torn or
cracked subframe bushing can prevent costly subframe repair and
welding.
  
Ripped or Failed Guibo
A torn guibo
(Flex Disc) will result in a perceivable 'drivetrain elasticity.'
Acceleration will be preceded with a loud clunk as the guibo bolts bind
together.
 
Dirty Automatic Transmission Fluid or Clogged Filter
Hesitation
and/or hard shifting could be the result of dirty and old automatic
transmission fluid or clogged transmission filter.
Water Pump Failure
Water
pump failure is without a doubt the easiest way to cause extensive and
expensive damage to your BMW. The main symptom will be a rapidly
overheating motor. What occurs is that the bearing or impeller on the
stock pump, breaks, completely disabling the cooling system. If you
ever see the temperature gauge on your BMW climb above the 3/4 mark,
TURN THE CAR OFF IMMEDIATELY AND
CALL A TOW TRUCK!!
We
can't stress this enough. Failure to catch the overheating motor in
time can result in a warped head or even more severe engine damage. We
recommend changing out the waterpump in six cylinder cars every 60-80k.
Cracked Radiator Necks
BMW loves
their plastic radiator tanks....Unfortunately...The plastic around the
radiator necks become brittle and crack with age, often without warning
(see warning above.) Radiators should be thought of as 80-100k mile wear items.
Trust us, this is cheap insurance!
Fan Clutch Failure
Most
fan clutches fail between 80 and 100k miles. They provide the primary
cooling for your car, and are easy for us to diagnose.
Accessory Belt and Tensioner Failure
Worn
tensioners and idler pullies will sound like a squealing noise from the
engine bay. Belts should be inspected for cracks regularly. If a belt
happens to snap, the cooling system will fail as the water pump will
cease to operate. Power steering and the alternator will also fail to
work. Again, pull over and shut the car off immediately should you
suspect a belt failure or see the temperature gauge rise past the 3/4
mark.
Leaky Valve Cover Gaskets
Prevalent on
all BMWs, a burning oil smell could indicate a leaky valve cover
gasket. If the condition continues unchecked, oil can seep into the
spark plug holes and damage the ignition coils, resulting in costly
replacement. Replacement of this inexpensive gasket is a good idea when changing sparkplugs as the coilpacks will already be out.
O2 Sensor Failure
Poor mileage,
poor idle and flat spots in the power curve could be caused by bad O2
sensors. Even if your car isn't throwing a check engine light, they
may not be performing optimally. BMW recommends replacing the O2
sensors every 100k miles. Extended high-RPM running/racing and
high-performance chips may shorten the replacement cycle.
Electrical Relay Issues
The relays
throughout the car were soldered with an automated process that wasn't
designed with solid-state components in mind. The lugs on the relays,
especially those for the headlights (located in the LKM) and the
taillights (the mustard relay) are much more massive and never got
enough heat or solder to form a good joint at the factory. They can
easily be resoldered, saving over $400 for the LKM or $60 for the
mustard-colored relay. (Thanks to MichaelY)
Power Seat Issues
The cable-
housings in the power seat assemblies also stretch, creating all sorts
of problems. (Thanks to Michael Y) Parts are readily available, but
somewhat pricey. We recommend this as a DIY project as paying someone
like us to fix a problem like this can be quite pricey!
Pollen Filters
If the flow of
air out of the air conditioning and heater system is not as strong as
it used to be, it strongly suggests the pollen microfilter of your car
has become dirty and clogged over time. A damp and musky smell can also
indicate a dirty filter. This is a service II replacement item.
|
