  We study three-body collisions within ultracold mixtures with resonant
interspecies $p$-wave interactions. Our results for the three-body effective
interaction strength and decay rate are crucial towards understanding the
stability and lifetime of these dilute quantum fluids. On resonance, we find
that a class of universal scattering pathways emerges, regardless of the
details of the short-range interactions. This gives rise quite generally to a
remarkable regime where three-body effective interactions dominate over both
inelastic decay and two-body effective interactions. Additionally, we find a
series of mass-ratio-dependent trimer resonances further from resonance.
