DB9 Door Check Arm Replacement
It
doesn't matter from what era, brand, or continent you're talking
about. If you're talking coupes, specifically coupe DOORS, we're talking
big! Even on a two-seat car, the doors seem to so long. A
four-seater, even longer! This makes parking lots a dangerous place along
with tight garage quarters, and on sports cars, high curbs. I'm not sure
if Aston Martin started their upward swinging doors to be different, or to
solve a problem. With the introduction of the DB9 Aston Martin took their
long coupe doors and started opening them upward at a slight angle. This
is yet another beautiful and unique spin on a rather normal car operation.
With
this new upward swing, Aston now had to compete with another law. This
being the law of gravity. Normally, car doors open on a flat plane
parallel to the ground. When open, they usually stay open due to a door
check strap. This is a flat bar that has detents and some sort of spring
force against them to hold the door in a few different positions. This
simple design is not enough to hold up against gravity. This gas strut design is used in many other
vehicle applications like on your engine bonnet and to hold up your rear
liftgate. When they wear-out they can be
quite a nuisance. And in some cases, not
holding up a liftgate or a strut giving out at the wrong time can be dangerous!
We’ll
give a brief outline here with pictures of how to replace the Aston Martin DB9
door check-arms (the V8 Vantage is very similar). The job can be done with some patience, a few
basic tools, and the help of a friend.
You
will need:
- T30
Torx bit or socket
- Long
narrow screwdriver or long straight pick 5” in length or longer
- Trip
pry tool
- 22mm
lug nut socket
- Torque
wrench
- Jack
with block or wood or hockey puck
- 2 Jack
stands
Park
your DB9 in a space that can allow both doors to open all the way. Loosen both front wheel lug nuts by one-half
to three-quarters turn. Yes, I am
recommending you loosen your lugs BEFORE lifting your car. This will use the vehicle’s weight to hold
the wheel in place for you while you “break” the lug nuts loose. This causes no harm to any components at
all. Use your jack and a protection pad
like a hockey puck to lift the front of your car up and place jack stands under
the chassis channels or the front lower control arms. Remove the front wheel lug nuts and
wheels. Remove both front fender liners
with the T30 socket. There are a lot of
fasteners here. My picture shows the
entire wheel arch liner removed.
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Once
you’ve done a set or two of these, you may consider only removing the rear
portion of the fender liner and pulling it forward over the brakes to gain
access to the door check arms saving you the time of a dozen fasteners. Locate the check arm in the door jamb area
and inside the wheel arch cavity. The
best reference here is your new check arms.
Look at the ball-ends and see a small metal strap that is the shape of a
“C” that clamps perpendicular to the gas strut.
Do not remove this from your new arms at any point – it is not
necessary. Locate these clips at each
end on your existing check arms and use the screwdriver or pick to pry under
these clips and slide them forward or backwards. Just a few millimeters of movement is all you
need. But since you’ll be throwing these
away with the old struts, feel free to pry them all the way off. They are spring loaded so be careful of
flying objects! Use the trim tool to pop
the ball-ends off of the ball heads.
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You
will see that there is a channel that the check arm moves within. Have your friend position and hold the door
open to just the right point where the gas strut can come completely off of the
ball head and be removed. While your
friend is in the perfect spot, grab your new gas strut and snap it right in
place. The metal “C” clips with
naturally expand and then clasp over the ball head and you will be rewarded
with an audible “click” when fully seated.
As always, reverse the removal process to assemble your car. Hand tighten all your lug nuts as much as
possible. Ideally, gently lower your car
until the tire kisses the ground and then at that point, torque the lug nuts to
100ftlbs.
All
done! Time to get into and out of your
car
without a big door giving you an extra nudge.