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7 Nov 04
- Disassembly
The bolts
holding the splash guards have threadlocker on them,
some heat was necessary to remove them.
After
that we removed the shafts from the hubs.
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Once the
shafts are out, the wheel speed sensor ring can
easily be knocked off with a mallet.
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This wheel bearing
is junk. The wheel bearing can be removed with a
press.
We carefully
heated the knuckle to expand it a bit and the bearing
came out easily.
Tip:
Many aluminum alloys are heat treated at a low temperature,
sometimes as low as 300 degrees (artificial aging).
Use caution when heating aluminum parts so as to
not over heat them, it will ruin the heat treatment.
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Warning:
If you press the bearings out without heating
the knuckle, be sure to support the knuckle
around the bearing area. Its possible to
spread the legs and damage the knuckle with
excessive force. |
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The old
wheel studs were pressed out, then the hubs sandblasted.
The hubs were drilled with the new bolt pattern
4.5". We used Dorman number 610252 1/2-20
x 1 15/16 studs, the serrated ends are .5890" in
diameter, a 37/64 (.5781) bit was used, which gives
a .0109 interference fit.
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The new
studs are pressed in and the hubs are ready for
paint.
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8 Nov 04 - Bushings
The old bushings
are removed, they are bring replaced with
polyurethane bushings from
VPM. They recommend a 2 jaw puller, but a small
3-jaw will work just fine. The polyurethane
bushing gets pressed into the knuckle with a bolt,
nut and washer and lots of grease. It will take
a lot of force to get it started, you'll think the
bushing is going to tear, but it won't. The trick
is to insert the metal sleeve into the bushing first.
It will help keep the bushing from deforming.
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If the bushing gets cocked but
is going in, keep going - it should
straighten itself out as it goes in.
A few whacks with a rubber mallet may
also get it straight. |
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The bearing
gets pressed in, be sure to only press on the outer
bearing race. The bearing is a PTC, number PT513058.
When
pressing the hub in, support the inner race
of the bearing from the other side.
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Done!
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30 Nov 04 - Diff Mounts
The
rubber mounting bushings for the differential were
shot, so so we turned some new ones out of 6061-T6
aluminum.
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5 Dec 04 - IRS Gear Change
The diff is opened and the bolt
holding the pin is removed.
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The pin slides right out,
the spring comes right out, and the gears are tapped
around until they can be removed. |
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The gears and clutch packs
are removed.
After everything was apart, we
cleaned it thoroughly.
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The friction disks are
scored.
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There was a little bit
of metal caught between a friction disk and the
shim. We are going to reassembled the pack with
the stock configuration. |
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Using the F150 spring
or the "performance stack" is said to cause locking
problems and understeer.
The carrier is removed
from the housing and the bearings removed. We were
unable to get a bearing puller or separator under
the carrier bearings, we ended up cutting them off
with a Dremel tool.
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17 Jul 05: Came across a trick
on an internet forum to get the carrier
out of the housing: block the
carrier from turning and then turn the
pinion, the carrier will crawl right
out of the housing.
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The new bearings are pressed
on the carrier.
Note the size difference
between the old (right) and new pinions. We are
changing from a 2.73 to 3.73. Ought to add lots
of zip!
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The old pinion bearing
is honed out so it slides on the pinion shaft easily.
It is used for all of the setup. The new bearing
is installed after all of the setup is done. |
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The preload is set
without a crush sleeve, the crush sleeve
will be added during the final assembly,
along with a new nut. |
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We made a plate that bolts
to the housing to measure the pinion depth.
For more detailed info go here and
here. Thanks to these folks for figuring this
out!
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We ended up
reusing the original shim which was
.0245 in thickness. Supposedly, this
is pretty common practice in Fords. |
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Here's the setup we used
to measure backlash. With the old bearing it measured
.0095.
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After we assembled
it with the new pinion bearing, it measured
.0105, both well within the specs of
.008 to .014. |
We had to make large
bar to hold the pinion while we tightened
the nut to compress the crush sleeve. |
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We soaked the friction
disks for about 2 hours in friction modifier and
gear oil. |
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The pack and gears
are installed in reverse of the disassembly.
We used a hose clamp to compress the
spring while it was inserted in place. |
We ended up with
the "competition" wear pattern on the
ring gear teeth. But is not visible
in the above picture, I took the picture
after we cleaned off most of the gear
marker. |
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Breather is made from
a bronze filter. We threaded the housing were
the plastic breather tube had broken off and used
a fitting to connect the hose. |
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And my helper takes a
break.
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5 Dec 04 - IRS CV Joints
As soon as the CV boots are removed
from the axle, we wrap tape around the bearing races
to keep the needles in place.
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Most people yank off the
joint with a gear puller, but if you slide the inner
clip up a little, you can push the joint back a
little. The small end clip will pop right off and
you can just slide the joint off the shaft. |
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We used the infamous pipe
drop method to remove the joint.
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Cleaned, painted the housing.
Repacked the bearings with grease. (One pack of
grease in each knuckle, do not overfill, otherwise
you run the risk of blowing out the boot.)
Re-assembled the axles with the new FFR supplied
shafts. |
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The clamps are tightened
and we are done.
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The differential in the
frame. Hopefully for the last time. |
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