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BMW E39 5-Series & M5 Front Wheel Bearing Replacement
(Model Years 1997 - 2003)
by Dave Zeckhausen
How to determine if you need new wheel
bearings
E39 5-Series and M5 front
wheel bearings are not known for being robust and
are common replacement items for racers. If you experience a low rumbling sound,
as if you have studded snow tires or if you experience
pad
knock-back, it may be due to bad wheel bearings. If you
have high mileage (75,000 +), it is a good idea to
replace the wheel bearings as a preventative measure while you are performing
other work with overlapping labor, such as shock or brake
replacement.
If you have no symptoms and
are not performing maintenance with overlapping labor, we do not suggest bearing
replacement simply due to high mileage. Occasionally, E39 bearings have
been known to last beyond 130,000 miles. Save your money and spend it on
things that really need replacement!
Zeckhausen Racing has better pricing than most dealerships
on
BMW E39 5-Series and M5 front wheel bearings and associated hardware.
The M5 uses different front bearings than the non-M5 models. Make sure you order the proper bearings for your model. See details and
installation instructions below.
* Pad knock-back occurs as the
result of high lateral g-force from sweeping,
high-speed turns. The wheel bearings/hubs deflect and the rotors
push the pads back. Then when the car is pointed straight,
there is a gap between the pads and rotors. The next application of the brakes
results in significantly longer pedal travel, as the pads move to
close this gap. When unexpected, knockback can be a rather
startling experience.
Parts Required
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Original BMW Part Number |
Description |
Retail Price |
Zeckhausen Racing Price |
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31-22-1-093-427
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525i/528i/530i/540i Wheel Bearing
(1 per side)
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$247.00
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$145 each |
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31-22-2-229-360
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M5 Wheel Bearing
(1 per side)
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$260.00
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$174 each |
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31-20-6-779-384
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M12 x 1.5 (55mm long) bolts
(4 per
side) |
$3.47
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$2.25 each |
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31-30-6-779-823
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M12 x 1.5 (95mm long) pinch bolt
(1 per
side) |
$3.25
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$2.50 each |
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33-32-6-760-374
|
Self-locking nut for pinch bolt
(1 per side) |
$3.25 |
$2.50 each |
|
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QTY(4) Bearing Bolts with Loctite
QTY(1) Pinch Bolt
QTY(1) Nut for Pinch Bolt |
|
Required Hardware (1 set per bearing) |
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M5 wheel bearings have the same internal design as 528i/530i/540i bearings; however, they have three raised
dowel pins which mate with matching holes in the M5 rotors. M5
bearings will not fit an E39 525i, 528i, 530i, or 540i with stock
brakes.
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If this is your first time changing
E39 wheel bearings, you should budget three hours for
the job and plan on two hours for the first side and one hour for
the second. Subsequent bearing swaps take about 45 minutes per side,
assuming you have air tools. |
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The wheel bearing/hub assembly is
secured from behind by four bolts.
Two of the bolts are easily accessible. The other two are blocked by
the shock absorber. This turns what should be a 5-minute job into the more
complicated process documented below.
If you are contemplating
replacement of your front shocks, there is almost 100%overlapping
labor with the bearing replacement, so you should consider doing both at
the same time.
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Installation Instructions
Safety Warning:
Working on your own car can be dangerous.
Even quality jack stands can collapse if not positioned properly, and a floor
jack can fail suddenly and without warning. You can be seriously injured
or even killed if you do not follow proper safety procedures. Please use
both a floor jack and a pair of jack stands to support your car so a
failure of any single support is less likely to result in the car falling on
you! Zeckhausen Racing LLC assumes no liability expressed or
implied for the improper installation or use of these components.
Note: The
following steps are performed on a 540i and are the same for the M5. The 6-cylinder models
(525i, 528i, 530i) have a different suspension configuration and these
instructions, while close, do not apply exactly. You may wish to
consult a service manual or a BMW mechanic before attempting this
service.
 Place the car on jack stands and
remove the front wheels. Remove the brake calipers and rotors.
I've upgraded to a big brake kit, which is
why my brakes look different. Be careful of the black metal dust shield,
which can be sharp and may cut your hands if you aren't careful.
If you are
installing a big brake kit and your car has more than 60,000 miles,
it is a good idea to change your bearings at the same time.
The factory shock absorbers are the same part
number for
left and right sides. Marks on the back of the strut
("L" and "R") are lined up during installation with a slot on the back of
the steering knuckle. Rather than using those marks, it's
easier to draw your own with a marker. Clean the dirt off and mark one or two vertical lines on the strut and the aluminum
knuckle.
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A closer view of the alignment marks. A horizontal line
is not required since the strut has a shoulder that sits firmly in the
knuckle. Also, the strut will have a sharp boundary between the
clean and dirty sections, so it will be obvious when it is seated fully
in the knuckle.
Once you've marked the strut, remove (and discard) the pinch bolt,
which is shown to the right and slightly below the alignment marks.
Use a wrench on one end to keep the bolt from rotating
as you remove the nut.
The pinch bolt holds a small
bracket that supports the ABS cable and, on the driver's side, the brake pad
wear sensor cable. After removing the pinch bolt, simply push this
bracket out of the way.
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 Remove the
18mm nut and bolt holding the
front lower control arm to
the chassis. A good whack with a rubber mallet should pop the arm
out. Label the bolt
so it isn't confused with the strut pinch bolt removed in
the previous step. When reinstalling, the bolt goes in from the rear and the nut faces the front of the car.
Note: If your BMW has auto-leveling Xenon headlamps, you will need
to disconnect the suspension height sensor from the passenger's side
control arm.
Remove the nut from the swaybar end link where it attaches to the
aluminum bracket. Use a 16 mm open end wrench to
prevent the stud from turning while you remove the nut. Wiggle the end-link
loose and push it out of the way. You may need to compress the
suspension slightly with a floor jack in order to get the end link
loose. Push it out of the way.
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A closer shot of the swaybar end link. The 16 mm wrench
is placed BEHIND the bracket to keep the stud from rotating while the socket
is used to remove the nut. |
Spray WD-40 or other lubricant
on the lower part of the strut so it will be easier to slide out of
the knuckle. Be careful not to wash away your alignment marks!
Grab the steering knuckle and pull it down as far as you
can. Your instinct will be to try to turn the knuckle side to side,
but it is held firmly in place by the control arm and can't turn.
Instead, grab the strut housing and turn the strut side to side while
you pull down on the knuckle. This is where it helps to have a
second person.
Pull it down far enough that you can access the four bolts
holding the bearing/hub assembly in place.
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 This is a view from behind.
The knuckle has been pulled down so the strut is no longer blocking access to the upper
two bolts. Be careful not to damage the ABS sensor wire.
An air wrench is helpful to remove these bolts, since the factory
used a thread locking compound and the bolts are very long. You'll
be sweating if you have to remove these bolts by hand. Depending on the
age of these bolts, you may have to fight them with a breaker bar.
They do not want to come willingly!
Discard the bolts after
removal. They should be replaced. Note the orientation of the
bearing assembly.
Install the new bearing assembly
in the same orientation as the one you just removed using
four new bolts. It only fits in one direction because the bolt holes are not
spaced evenly. The new
bolts come with dry Loctite already applied.
If you find yourself reusing the old bolts (not
recommended), apply
thread locking compound. Tighten each bolt to 75 lb-ft.
After pushing the knuckle back up, make sure the marks on the strut
align with the marks on the knuckle. Use a floor jack to compress
the suspension, but be careful not to lift the car off the jack stand.
Position the lower control arm back
into the chassis bracket and slide the original bolt through and attach
the nut. Don't tighten yet until the suspension is compressed in the
next step. The chassis bushing will be damaged if you tighten this
fastener while the suspension is in full droop.
Compress the suspension with a floor
jack until the car is just about to lift off the jackstand. Torque the lower control arm bolt to 60 lb-ft.
Install a
new pinch bolt and nut and torque to 50 lb-ft. Don't forget to
reinstall the bracket, which is held in place by the pinch bolt.
Insert the stud from the sway
bar end link into the bracket and tighten, using a 16mm wrench to keep
it from rotating, while you
tighten the nut to 30 lb-ft.
Congratulations! You've just
changed your own wheel bearings.
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