The right rear
wheel seal on the MOG had a slow leak from the time we got the
truck. The leak easily kept from being a problem with frequent
level checks. In the spring of 2003 it started to get worse,
so we decided it was time to replace the seal.
Here are the tools required to do the job. We thought we could
do the job with regular pullers, but we broke three pullers without
budging the hub, so had to track down the puller. After many
difficulties, we finally got our hands on the hub puller (top) and
reinstallation tool (second from right), thanks Scott!
Anyone within a reasonable shipping distance of Calgary who needs to
change a wheel seal is welcome to contact us, we'd be happy to rent
out our tools.
Getting the gland bolt undone is the first challenge. The
torque spec. on that thing is 750 - 1000 ft-lb. It is
important to remember to break the bolt loose before loosening the
wheel or jacking up the truck. That is just too much force to
apply without the tire firmly on the ground, supporting the
truck. After bending down the tab on the lock plate, we used
our 3/4" t-bar handle & socket with Sharon standing on a 4'
snipe & Keith lifting on a 6' snipe to break it free. That
Snap-On t-bar handle now has a slight curve. After breaking
the bolt free we removed the wheel & drum, and removed the 55mm
(2 3/16") bolt.
The puller bolts to the hub using the lug nuts. The same
socket that fits the gland bolt fits the hub puller. It took
rather a lot of force to crack the hub free.
Once the hub started to pull with the t-bar handle, we switched to
the ratchet to make the job a little easier. With the fine
threads on the puller, it took a long time to pull the hub off, but
it came off well.
Yuck!!! That seal had been slowly leaking for a long
time. Notice the inner end of the puller bolt still inside the
hub. The bolt rotates within the end which sits in the end of
the stub axle shaft. The four little flat spots allow you to
leave the roll pins in place, if they choose not to pull out with the
washer ring which sits under the lock plate, under the head of the
After a lot of cleaning, you can see the weep holes in the hub, from
both inside and outside.
Here are a couple of views of the old seal, still in place.
Removing the old seal was relatively easy with the help of a small
gear puller. In order to get the jaws on the inside of the
seal, one arm was unbolted, both jaws were slipped into place, and
the puller bolted back together.
Underneath that seal is a rather large bearing.
One of the hardest things to find out in advance of pulling the
seal, was what size it is. Now we know that it is
90x120x13mm. The thing we weren't able to find out until we
had the seal out, is that it is a double lip seal. Not
only does that seal try to keep the oil in, it tries to keep dirt
& water out.
So, after gently tapping the new seal into place, we're ready for
We carefully cleaned up the splines of the stub axle, and put on a
little bit of Lubriplate to aid the reassembly process.
The bolt in the center of the reinstallation tool threads into the
stub axle where the gland bolt goes, and is held with the smaller
crescent wrench so that you know you're not going to damage those
threads. This is where the 2' crescent wrench comes in, you
can't use the socket on the big nut that pushes the hub back into
place, although it is the same size.
It is a slow job to get that hub pushed back on, a lot of force is
required on that big wrench. The reinstallation tool is
designed so that when the hub is in place, there is about 1/2mm of
clearance between the end of the roll pins & the pushing
surface, just enough!
Here is the hub back in place, no more oil leak! Our 3/4"
torque wrench doesn't go high enough for the gland bolt, so we did
it as far as we could go with that, then went a bit further, that
thing isn't going anywhere.
Our luck with locking plates isn't very good, the little tab on the
inside that holds it in place broke off of the old one, and promptly
broke off of the new one too. So, our locking plate is held to
the big washer on the end of the stub axle with a small weld bead.
After breaking three pullers and then finally managing to buy the
appropriate tools, the job only took something like 2 1/2 or 3
hours! That made the heavy, expensive tools worth every penny.