Now that the wheel is removed from the truck we can get busy to remove the tire from the rim. This could be a potential dangers peace of work. The rim of a gmc exist out of two pieces the rim itself and a ring that locks the tire on the rim. This ring is the dangerous part of the wheel. This ring is hold only on its place by a little groove in the rim and its constantly under strain from the tire pressure. As long as the tire is inflated the ring wants to come off. Thus before we are doing something we deflate the tire so we can work safely.
Never ever inflate the tire again without any precautions made!!!
We shall look ad that later...
Now that the tire is deflated we can work safely because the ring isn't under strain anymore.
The ring has a hole for the tire-lever to the left and right of this hole is the ring smaller (unfortunately not on picture in yellow circles) these are necessary to remove the ring from the rim. As you can see one narrow is closer to the hole for the tire-lever this is the place where we first get the ring over the rim out of the groove.
Marked with the red arrow the groove who's holding the ring in place. The green arrow indicates another groove that allows us to create some more space as we put the ring in there we can move the ring a little more to the centre of the rim.
Now the tire is deflated we can push the ring a little down ad
the red arrows so we create a little space. (see previous picture green arrow)
Now we can move the ring by hitting with a hammer at the spots of the red
arrows. You move as it were the ring towards the yellow circle. By doing this
you create at that spot a little more room to maneuver the ring. And let just
there be the smaller section of the ring. Now you can by putting the tire-lever
in the hole ad the green arrow jerk the ring over the groove.
With a hammer putting the ring down and towards the middle.
You create some room ad the other side
Tire-lever in the hole
jerk a little
And get the ring over the rim out of the groove
Just do that all around
And the ring is off the rim and the tire is free to removed
Now i tell you this easy but i think when you do this the first time it is a hell of a job. The first tire we did took us a hole day. Because we had no idea how to tackle this problem. But after a lot more tires we got the hang of it and it goes every time quicker.