Do you see gear oil leaking form the rear of your SUV or light duty truck? Do
you wonder how difficult it is to change the axle seal and bearing? I am a 25 year master tech
and I have created this article and video just for you to be able to do your own
repairs on a Chevy, GMC, Cadillac, Ford and Lincoln SUV's and trucks or at least
see what you are paying for when you have taken your vehicle into the repair
shop. These vehicles use the basically same differentials in the 1500 and F-150
half ton series.
Using everyday mechanics tools you to can make these repairs by following my
instructions while saving a considerable amount of money and having the
satisfaction of doing the job right.
The job might seem difficult but once you know the information in the video
below and added tips the video might have missed in the following article you
will feel more confident the job can be done.
To retain the parts for this job visit Amazon, where you can get GM and Ford
OEM factory parts for the same wholesale price the repairs shops pay for them.
You will need
Replacement axle seal and differential gasket
Screw drivers set
Protective gloves and eyewear
Large pry bar
Fluid catch basin
Oil catch basin
Now sit back and relax and watch my son and I do the job, once the video has
finished continue on reading through the article, let's get started.
When doing this repair remember safety first, never get under the vehicle
unless jack stands are in place, I want you to use safety as a normal practice
anytime repairs need to be done as you learn automotive repair.
Before work begins, park the car on level ground while blocking the front
Identify the side of the differential you see the leak on and will be
performing the repair. While the vehicle is still on the ground, break the lugs
loose by pushing downward on the lug wrench this will help you use the leverage
of your body weight and save you from hurting your back, instead of pull upward.
Once loose, place the jack in the center of the differential pumpkin and raise the
vehicle off the ground, install jack stands on either side of the axle tubes.
Continue removing the lugs and then remove the tire, then slide the tire under
the vehicle for an added measure of safety.
Retainer clips are used to hold the brake rotor on during manufacturing, use
a pair of side cutters, pick or small flat blade screw driver to remove them and
discard, this can take some doing but hang in there.
Next, locate the inner brake caliper mounting bolts (15mm) to loosen and
remove both upper and lower units. At this point it's a good idea to put all
removed bolts and clips into a plastic container so they don't get lost.
Grasp the caliper and with a rocking motion back and fourth slip the caliper
upward to remove and set it securely out of the way. Don't allow the caliper to
hang by the brake hose because it can become weak and fail.
Then, carefully remove the brake pads making sure to set them in a clean dry
place as not to get them dirty or greasy which will affect their performance. If
these pads are worn now would be a good time to replace them on both sides.
Again, Amazon is the best place to find OEM replacements.
Now it's time to remove the brake caliper mounting bolts, these bolts can be
fairly tight because the factory might use thread lock during assembly so get a
good grip on the wrench or ratchet while applying pressure. Also be sure the
tool is squarely on the head of the bolt to avoid stripping. The bolt size is
Now that the caliper mount has been removed the brake rotor might be stuck on
the axle flange due to rust and the pressure of the lug nuts. Use a hammer to "shock" the rotor
loose by striking it between the wheel studs. The rotor will then come off which
is heavy so get a good grip on it before you remove it.
If the emergency brake shoes are worn or contaminated with gear oil this
would be a good time to replace them with new units. After the brake rotor has
been removed, locate the small bolt that holds the emergency brake shoe in place
using an 8mm 1/4 drive socket and ratchet to turn the bolt counterclockwise for
Once the retainer has been removed,
lift the brake shoe from the axle assembly. This will take some doing, start by
lifting one end of the shoe over the axle flange and then following it around in
a circular motion which will enable you to remove it. If the shoe is okay you
can leave it in place while replacing the seal.
Now its time to get under the vehicle and remove the rear differential cover,
begin by loosening the bottom three bolts, this will hold the cover in place
while removing the remainder of the bolts. Have a fluid catch basin ready to
collect the gear oil which should start to flow out from the cover.
If gear oil doesn't start to leak you must help break the seal by using a
flat blade (standard) screwdriver and allow the gear oil to drain out. Once most of the gear oil has drained
into the catch basin, remove the remaining three bolts to remove the cover, use
a large screw driver to continue releasing the seal.
Continue to remove the cover and place it off to the side, this cover will
need to be cleaned which will be done in later steps. Once the cover is removed it
will exposing the inner workings of the differential.
After inspecting the inner workings, rotate the driveshaft until the carrier
pivot shaft bolt is exposed, this can take a few turns of the driveshaft before
seeing it. Stop turning when the bolt is near the top of housing. Also, keep
your fingers clear while rotating the gear set to avoid injury, these gears can
Once the carrier bolt has been located, use a small ratchet or wrench (8mm) to loosen and remove the bolt.
This bolt can be snug so make sure your tool is squarely on the head of the bolt
to avoid rounding which will make the job much more difficult.
Once the pivot bolt has been
removed, reach your hand down around to the bottom of the carrier and use your
finger to pop the pin upward while grabbing it with your other hand. You might
need to maneuver the driveshaft to gain enough clearance to allow the pinion
pivot to slide completely out.
After the pinion pin has been
removed, again rotate the driveshaft until the "C" clip access port appears.
Watch the unit as you slowly turn it, if the spider gears (small gears) start to
move into the port turn the axle with the driveshaft to keep the gears in their
Next, at the axle flange (wheel side) push the axle inward toward the
differential, the axle will move inward slightly. This is to allow enough
clearance for the "C" clip to be removed which holds the axle in the
Using a small screwdriver or magnet work the metal "C" clip in a circular motion, this will enable you to remove the
clip which will release the axle from the differential, this can take a little
time so hang in there.
Once the C clip has been removed from the carrier check the clip for wear and
scoring and replace if needed, this will be a dealer part.
Now that the C clip has been removed grasp the axle at the flange
and pull outward, the axle should slide out completely from the differential
housing, use a shop towel around the axle as it's being removed to wipe residual
gear oil to keep the mess down to a minimum.
After the axle has been removed
inspect the bearing and seal surface to check for wear/scoring and replace if
axle was worn you would see an obvious groove in this area. Do not reuse the
axle at this point because the new seal will fail prematurely. These axles are
available at the dealer for about $200.00 bucks.
Now we are ready to replace the seal, use a large pry bar to leverage the
seal out of the differential housing, you can also use a seal puller but I have
found this method works pretty good.
Once the seal has been removed, inspect the differential seal house flange
for damage and if so, this may allow the new seal to leak in which case use
silicone rubber to help fix the problem when installing the new seal. Also check
the axle bearing for wear or pits in the rollers which means it needs to be
replaced, reference the video above. When replacing an axle
bearing a special puller is needed to extract the bearing from the housing, it
can be reinstalled by using a hammer and a punch, or bearing driver.
Using a shop towel, clean the seal
mounting surface which will ensure proper installation. Use carburetor cleaner
to make sure the surface is clean and dry before you begin reinstalling the
Once the surface has been cleaned,
match the new seal to the old unit and apply sealer to the differential housing
Next, set and hold the seal in place, then drive the seal into the
differential housing using a flat bar to hammer against while installing the seal,
continue this operation until completely installed and flush against the housing
and seal lip, this seal can only be installed one way.
After inspecting the axle for damage and you see that it's okay to reinstall,
apply a small amount of gear oil to the bearing and seal surface. This will help
lubricate the surfaces and give you a better chance for the new seal not to
leak. Then carefully install the axle by holding it up not allowing the weight
of the axle to ride against the seal lip which will damage it.
While the axle is sliding inward you will need to push down on the bottom of
the flange while pulling outward on the top, this will lift the end of the axle
up and into the carrier. Also turn the axle slightly at the same time, this will
allow the axle spline to engage into the carrier. Then continue to push the axle
inward until it stops.
Check to see if the axle has been fully engaged into the carrier enough to
put the clip into place, now reinsert the C clip retainer onto the axle through
the access port, you can use a small pair of needle noise pliers if needed.
After the C clip installation is complete, pull the axle outward to lock the
C clip in place, then insert the pinion shaft, you might need to rotate the axle
to align the spider gears for the shaft to be installed, also turn the axle to
help, Take note of the shaft bolt hole so you can reinstall the bolt.
Example of bolt hole orientation.
After the shaft has been installed, insert the retainer bolt and tighten,
this bolt needs to be fairly snug.
After the axle has been reinstalled use a scraper to remove the old gasket and clean
the differential surface. Make sure this surface is clean from gear oil or it
will contaminate the sealer and possibly cause a leak. Use a shop towel to wipe
out the differential housing to help control additional oil.
Next, clean the metal debris from the differential cover magnet and continue
to clean the gasket surface with the scraper free from gear oil, use carburetor
cleaner to ensure no oil is present.
Then, install the new gasket using silicone rubber as a sealer, create bead
inside of the bolt holes to help stop leaks. Do not use cheap home grade sealer
you need to get the good stuff which costs a little more but is available from
Amazon, Home Depot or Lowes hardware stores.
Carefully install the differential cover as not to disturb the gasket
location on the cover. Excessive movement will cause the sealant to be less
Install the cover bolts and tighten in a star pattern. Bolts don't need be
super tight, just snug.
Once the cover bolts are tight,
remove the differential fill plug which is located near the driveshaft this will
be a 3/8 drive socket extension or ratchet head. Then install the gear oil, if
your vehicle has the clutch style posi-traction unit you will need to pour in an
additive which helps lubricate the clutches. Usually there will be a tag near
the fill plug that indicates what kind of oil is required.
The fluid level is full when gear oil
is dripping from the fill port, to double check the level gentle dip a finger
inside the port. Never turn driveshaft or axles when checking gear oil to avoid
injury from the gears. Reinstall and tighten the fill plug and you are all set.
Double check your work by looking for leaks at the cover. Safety return the
vehicle to ground level and take it for a test drive while listening for
abnormal noises, also recheck the differential for fluid leakage.
Use high quality silicon rubber to ensure a proper seal.
Always refill the differential with factory recommended fluids.
Differentials that are limited slip require a special fluid.
Use jack stands when working under a vehicle.
If the bolt breaks inside the carrier an air hammer can be used to
force outward (break) the pivot rod through the carrier, the pivot pin will need to be
replaced along with the bolt.
If you need additional information you have just read or seen please visit
our forum where thousands of questions have already been answered.