Hydraulic assembly

1. An assembly comprising:

a spring seat including an interior surface and a wall;

a spring seat insert including an exterior surface, an interior surface, and a second wall extending from the exterior surface to the interior surface, the spring seat slidable along the exterior surface of the spring seat insert to define an expandable fluid chamber between the second wall of the spring seat insert, the interior surface of the spring seat insert, the interior surface of the spring seat, and the wall of the spring seat;

a groove defined in the interior surface of the spring seat, the groove having a first vertical surface, a horizontal surface, and a second vertical surface extending from the horizontal surface;

a seal between the spring seat and the spring seat insert, the seal having a first end, a second end opposite the first end, a mating portion at the first end, a first flange disposed at the second end engageable with the horizontal surface and the second vertical surface, and a second flange disposed at the second end engageable with the second vertical surface and the exterior surface of the spring seat insert, the first and second flanges arranged to prevent fluid from exiting the fluid chamber; and

a mating insert separate of the spring seat, the mating insert disposed between the mating portion of the seal and the first vertical surface and the horizontal surface of the groove; and

wherein the seal is designed to allow sliding of the spring seat along the exterior surface of the spring seat insert when the seal is disposed in the groove in a first orientation and to prevent sliding of the spring seat along the exterior surface of the spring seat insert when the seal is disposed in the groove in an orientation transverse to the first orientation.

2. The assembly of claim 1 , wherein the mating portion of the seal has a width, and the second end of the seal has a second width, and a ratio of the width to the second width is substantially 37 percent.

3. The assembly of claim 1 , wherein the seal is dimensioned to fill the groove when the mating insert is disposed between the mating portion of the seal and the first vertical surface and the horizontal surface of the groove.

4. The assembly of claim 1 , wherein the seal is designed to seal the fluid chamber when the seal is in a first orientation and designed not to seal the fluid chamber in an orientation transverse to the first orientation.

5. The assembly of claim 1 , wherein the spring seat insert includes a fluid line that provides fluid to expand the expandable fluid chamber.