A boot seal for a joint assembly connecting first and second machine components pivotable relative to one another in a finite angular pivoting range, the boot seal comprising: a resilient seal body defining a center axis and including a body wall extending between a first axial body end and a second axial body end and circumferentially around the center axis ; the first axial body end defining a larger diameter circular opening and the second axial body end defining a smaller diameter circular opening ; a first sealing ring positioned at the first axial body end and including an exposed outer radial surface positionable in radial contact with the first machine component ; a second sealing ring positioned at the second axial body end and having an exposed outer axial surface positionable in axial contact with the second machine component ; and the resilient seal body further defining an axial body length, and being in a rest configuration where the body wall forms a curvilinear taper extending a majority of the axial body length from the first to the second axial body end , and the resilient seal body being deformable in response to axial compression between the first and second machine components to a squished configuration where the body wall forms a radially outward bulge storing an energy of the axial compression to bias the second sealing ring against the second machine component , characterised in that the body wall further includes a longer wall section adjacent the first axial body end, a shorter wall section adjacent the second axial body end , and an outer wall surface having a convex axial profile within the longer wall section and a concave axial profile within the shorter wall section ; and in that the body wall further includes an inner wall surface having a concave axial profile within the longer wall section , and a convex axial profile within the shorter wall section . a resilient seal body defining a center axis and including a body wall extending between a first axial body end and a second axial body end and circumferentially around the center axis ; the first axial body end defining a larger diameter circular opening and the second axial body end defining a smaller diameter circular opening ; a first sealing ring positioned at the first axial body end and including an exposed outer radial surface positionable in radial contact with the first machine component ; a second sealing ring positioned at the second axial body end and having an exposed outer axial surface positionable in axial contact with the second machine component ; and the resilient seal body further defining an axial body length, and being in a rest configuration where the body wall forms a curvilinear taper extending a majority of the axial body length from the first to the second axial body end , and the resilient seal body being deformable in response to axial compression between the first and second machine components to a squished configuration where the body wall forms a radially outward bulge storing an energy of the axial compression to bias the second sealing ring against the second machine component , characterised in that the body wall further includes a longer wall section adjacent the first axial body end, a shorter wall section adjacent the second axial body end , and an outer wall surface having a convex axial profile within the longer wall section and a concave axial profile within the shorter wall section ; and in that the body wall further includes an inner wall surface having a concave axial profile within the longer wall section , and a convex axial profile within the shorter wall section . <EOS>