Power to the Wheels!
Install and Hub Replacement
John Logan came over Saturday
(8-Sep-01) so we could install a Dana 30 Lock-Right
in the front axle of his ZJ. His Grand has over 125,000 miles, and
was in need of new front hub/bearing assemblies as well. Since we
had to pull the axle shafts to install the Lock-Right,
we replaced the hubs at the same time.
|Dana 30 Lock-Right
Available from KY
|2 Hub/Bearing Assemblies
for Dana 30
||Federal Mogul 513084
($105 at Advanced Auto)
($150 at Autozone)
|New ring gear bolts
REMOVING TIRES, CALIPERS
First order of business
is to jack up the front axle, set it on jack stands, and remove the wheels.
After that remove the brake calipers and rotors. The calipers are
held on with 2 13mm bolts from the back side. After removing the
bolts, compress the piston a little with a large C-Clamp. That releases
the rotor from the caliper. Then hang the calipers from the control
arm with a zip tie.... we did this, so the brake line wouldn't be stretched
Caliper removed and hung
on control arm.
PULLING THE HUBS &
If you are not replacing
the hubs, you can skip this next step since the hubs & shafts can be
pulled as one assembly. The next job is to unbolt the axle shaft
from the hub. First remove the cotter pin, nut cover and spring.
This exposes the axle nut (36mm). A air impact wrench makes taking
off that nut easy. If you don't have an impact wrench, it could be
a little tough.... that bolt is torqued to 175 ft lbs. A pry bar
placed between lugs, going down to the ground will hold the hub in place
while you put a breaker bar on the axle nut. A couple of lug nuts
on the studs will protect the threads.
The next step is to remove
the hub assembly. The hub is held in place with 3 13mm 12-point bolts.
Take these out, then tap out the hub assembly. The brake dust shield
will come out at the same time.
||Hub and dust shield removed
from knuckle. Notice the 3 bolt holes that hold the hub in place.
||Axle shaft, dust shield,
hub and rotor.
OPENING THE DIFFERENTIAL
Now the messy part... opening
the differential. To make life a little easier, pull the tie rod
off of the driver side knuckle. The tie rod sits right in front of
the diff cover, so tying it up out of the way gives you more room to work.
First pull the safety pin, and then remove the nut. Next use a puller
to press the tie rod end out of the knuckle.
||John removing the tie rod.
Next we removed the FourX Doctor
diff guard and diff cover. Leave a couple of the bolts in loosely,
so the entire cover will not pop off at once. Crack open one corner
and let the fluid drain into a pan, and then clean out the rest of the
oil with brake cleaner.
PULLING THE CARRIER
Next, note the orientation
of the carrier bearing caps. If you look closely at the picture
below, you will see stamps in each cap (circled in RED), and matching
stamps in the diff case. We took a close-up picture in case we didn't
keep the caps/bolts together correctly. The bolts/caps need to go
back in the exact way they came out, so the orientation is important.
They need to be put back on the same side, and in the same direction, so
don't flip them around. We loosened, but didn't remove, the bolts.
That way the carrier won't fall all the way out (on your head!).
||Close-up of the bearing
caps. Notice the T stamped in the left bearing cap (circled in RED),
and the matching mark on the diff case. The right side had a bar
stamped in it. Click on the picture for a close-up.
The next step was to remove
the carrier. Sometime this can be tough. You may need to use
a pry bar and a BFH. If so put the pry bar on the side, or behind
the carrier (top/bottom of the picture above) and pry against the case.
You may have to really hit the pry bar with a heavy hammer to get the carrier
to move, if its in tight. DO NOT PRY ON THE RING GEAR TEETH, OR SPIDER
GEARS. The carrier will come out easiest if it is pulled out square
to the diff case.... if it starts moving more on one side than the other,
you may need to pry on the other side to even it up. Luckily John's
carrier came out with one tug, and very gentle prying.... that might have
something to do with 125,000 miles. Once it is most of the way out,
we removed the bearing cap bolts, and laid them aside in proper orientation.
Then the carrier came right out. We sat the bearing races aside,
since they fall off easily.
REMOVING THE RING GEAR
The next step is to remove
the ring gear. It is held in place with 10 bolts. Before you
pull it, mark the position of the ring gear relative to the carrier.
We did this with 2 marks in case we rubbed one off.
||Carrier and ring gear marked.
We used white touch up paint
to put an X on the carrier and the ring gear, then put a dash at another
We used an air impact wrench
to remove the bolts. If you don't have air tools, you will probably
have to clamp the carrier in a vice to remove the bolts. Once the
bolts are out, you may need to tap the ring gear with a rubber mallet (or
piece of wood) to get it off of the carrier. The ring gear is brittle,
especially the teeth, so don't strike it with a hard hammer.
REMOVING THE CROSS SHAFT
& SPIDER GEARS
Next remove the cross shaft.
To do this you first have to tap out the roll pin that holds the cross
shaft in place. Insert a screwdriver into the whole on the top side
of the carrier, and tap out the roll pin. If you don't have a long
enough screw driver, use an old drill bit along with the screw driver.
The cross shaft should slide then, and you can remove the spider gears.
||Removing the cross shaft.
When removing the spider
gears, be sure to remove the thrust washers too. There should be
a washer behind each of the 4 gears. You will need the 2 end washers
(where the axle shaft slides in) to install the Lock-Right.
Next we cleaned off the carrier, the thrust washers, and Lock-Right
pieces with brake cleaner.
ASSEMBLING THE LOCK-RIGHT
You should first read through
the manual that came with your Lock-Right.
It contains detailed info on the installation, and this article is just
meant as a supplement, not a replacement. The pictures below are
of the Lock-Right assembled outside
of the carrier, for easier viewing. You will actually build the Lock-Right
in the carrier.
Coupler and Thrust washer
|First put a thrust washer on
each outside coupler, and put the couplers into the carrier|
Driver, pins and springs
|Next drop the pins into the
holes in the drivers (2 in each driver so they drop out of the way).
A little grease will hold these in place. Don't install the springs
(L-R) spacer, driver, spacer washer,
coupler, thrust washer
|Put the spacer and spacer-washer
inside the driver... again grease will hold it in place. The spacers
open towards the teeth of the driver, and should seat with the spacer-washer.|
|Apply a coat of grease to the
teeth of the driver.|
One half - driver, spacer, coupler
& thrust washer
|Now install the drivers onto
the couplers. You will have to do one at a time and seat the teeth
together. There isn't enough room to drop both in as one piece.|
with cross shaft
|Now rotate the driver/coupler
pairs so that you can install the cross shaft, and put the new hardened
cross shaft in place. You may need to slide the spacers out of the
way of the cross shaft.|
Installing pins and springs
|Now assemble the springs....
one small spring inside of one large spring, with a little grease to hold
them together. You should have 4 assembled springs.|
|Now the tricky part of installing
the springs. Slide the pins out of the spring window, and start the
spring into the window, into the other driver. Push it in place with
a small screwdriver, and make sure its seated all the way.... otherwise
it may pop out. Repeat for all 4 springs.|
|Now install the roll pin to
hold the cross shaft in place.|
REPLACE THE RING GEAR
After the Lock-Right
is completely in place, and the cross shaft is re-pinned, the next step
is to re-install the ring gear. First clean off the ring gear and
carrier so that no dirt particles are on the mating surfaces. Even
tiny specs of dust can throw off ring gear backlash, so get this thing
SPOTLESS. Don't even let lint from a rag stay on the surfaces!
Line up the ring gear marks with the marks you made on the carrier.
You may need to tap the ring gear with a rubber mallet to get it to seat
completely. If the ring gear is really tight, you can heat it up
in an oven. That will let it expand, and it should just slip right
on. Lining up the holes can be a little tricky too, so take your
time, because you don't want to cross thread the bolts. You shouldn't
re-use old ring gear bolts. I've heard stories of them snapping off
when re-torqued. Plus they are fairly cheap, so buy new ones, and
don't worry about it. Once everything is lined up and seated, put
in a few new bolts to hold it in place, and finger tighten them.
Put the remaining new bolts
in, but first apply Loctite to the
threads and finger tighten. Remove the bolts you put in above and
apply Loctite if you didn't originally.
We first tightened them all up to about 40 ft lbs, torqueing alternating
sides around the ring gear so that the ring gear is pulled in evenly.
Then we went back and torqued to 80 ft lbs, again working in an alternating
pattern, much like you would tighten the lugs on a tire.
We didn't have a vise handy,
so we clamped 2 long 2x4's together to hold the carrier. That way
one person can easily hold the carrier still while the other torque's the
||Reinstalling the ring gear.
Notice the X's are realigned. Torque to 80 ft lbs.
REINSTALL THE CARRIER
Its almost time to re-install
the carrier into the diff, but first clean it out well with brake cleaner.
Some oil & cleaner may pool up in the bottom, so be sure to wipe that
A rubber mallet will come
in handy when re-installing the carrier. If you don't have a rubber
mallet handy, place a 2x4 against the carrier, and tap the 2x4 with a regular
hammer.... that will soften the blow enough to not damage the carrier or
ring gear. Its a little tricky to get everything in, so having another
pair of hands helps. You need to put both of the bearing races on
the carrier, hold them in place, and then start the carrier into the housing.
It will go in easiest if you keep it square to the housing. While
one person holds it stable, have the other person tap it into place, working
side to side, until the carrier is completely seated. Once it is
seated, put the bearing caps back in place. Be sure to put them in
the correct orientation, referencing the marks we mentioned above.
Now torque down the bearing cap bolts and you're almost done.
||Carrier with Lock-Right
re-installed into diff.
REPLACE AXLE SHAFTS &
Now we will replace the
hub/bearing assemblies. First clean off the mating surfaces with
brake cleaner and a rag. These things tend to hold a lot of dirt,
so you may have to scrub for a minute. This would be a GREAT time
to inspect or change out your front axle U-joints since they are already
out of the axle. We didn't do it on John's, his appeared to be in
good shape, but we probably should have anyway just as preventative maintenance.
Now re-insert the axle shafts carefully. You don't want to damage
the inner oil seal (just outside the carrier), so very gently re-insert
the axle shafts.
Then apply anti seize to
the hub mounting surfaces, and to the splines on the axle shafts.
Nothing is worse than seized parts, so we really lubed them up.
||Anti seizing the hub mating
surface and axle shaft.
Now its time to install the
new hubs. The brake dust shields go between the knuckle and hub,
but we left them off of John's. The idea being that the shields just
hold in more dirt and mud against the rotors. If you want to put
yours back on, do it now. Now slide the hub over the axle shaft splines.
Once the splines are engaged, line up the 3 mounting holes with the holes
in the knuckle. Be very careful on the alignment, because you don't
want to cross thread a bolt here either! After the holes are aligned,
the hub should seat with just a little force, or maybe a mild tap of a
hammer. Apply anti seize to the 12 point bolts, and torque them down
to 75 ft lbs.
The next step is to install
the axle nut. First place the washer over the end of the axle shaft,
then get the nut started. The nut needs to be torqued to 175 ft lbs,
so holding the axle shaft still can be tricky. We placed a pry bar
between 2 studs, and against the ground to hold the hub & shaft still.
Then its easy to torque down the nut. After the nut is torqued down,
install the washer-spring, the castle nut cover, and finally re-insert
the cotter pin and bend the tabs so that everything is securely held in
place. If the pin hole doesn't line up correctly with the cover,
rotate the cover one notch and you should be fine. Worst case, tighten
the nut just a little more to get everything to line up correctly.
REPLACE ROTORS & CALIPERS
We're just about there!
The next step is to re-install the brake rotor and caliper. First
place the rotor on the hub assembly. Untie the caliper from the control
arm, and slide it over the edge of the rotor, and make sure that it seats
correctly against the knuckle. There are 2 slots at the bottom that
rest against the lower arm of the knuckle. Seat those first, then
push the top into position. Once its all lined up, re-install the
2 caliper bolts and torque to 11 ft lbs.
TEST THE LOCK-RIGHT
Next we re-installed the
tires so we could easily test out the Lock-Right.
The Lock-Right manual give a full
test procedure, but basically you are looking to see if the Lock-Right
really locks the shafts together, and to make sure that either side is
free to ratchet past the other side.
||Testing the Lock-Right
||Video clip 1 of Lock-Right
||Video clip 2 of Lock-Right
REPLACE THE DIFF COVER
If everything is working
correctly, its time to seal up the diff cover. Be sure the gasket
surface is clean, and no RTV is left on the diff surface, or the cover
surface. If you're going to use RTV for the gasket, apply a bead
around the entire circumference of the diff cover and let it set up for
about 5 minutes. If you're using a paper gasket, then you just need
to line it up with the bolt holes. After the RTV has set up, re-install
the diff cover and bolts. We also replaced John's FourX Doctor
diff guard at the same time. The cover only goes on correctly in
one orientation, otherwise the ring gear will be grinding against it (and
it probably won't seal up!) Torque the bolts down to 30 ft lbs.
Next, refill the diff with gear oil. We used 80w-90 and filled until
it started trickling out the fill hole. Once its filled, reinsert
the plug, and torque it to 25 ft lbs.
The last step is to reinstall
the tie rod end. Just put the end into the knuckle, start the castle
nut, then torque to 55 ft lbs. Install the cotter pin, and you're
done. You can set the Jeep down off of the jack stands. If
the hole for the pin doesn't line up, tighten the nut a little more....
never loosen a nut to get the pin to align.
Now its time to go out and
have fun!!! We tested it out a little in my yard, then took it for
a spin in 2wd on the road to make sure everything felt good. Once
you get it off road, you will really notice the difference. The steering
will be quite a bit heavier, and under steep descents, the steering may
actually bind up. You can work around this, by slowly rocking the
Jeep back and forth while continuing to turn the steering wheel.
Its slow, but it will work. Of course the big difference is the additional
traction! You'll be crawling over all kinds of big rocks now!
(from TJ service manual)
|Ring gear bolts
||70-90 ft lbs
||45 ft lbs
|Diff cover bolts
||30 ft lbs
|Diff cover fill plug
||25 ft lbs
|Hub bearing bolt
||75 ft lbs
||175 ft lbs
||11 ft lbs
|Tie rod ends
||55 ft lbs