you have a 99 tarago? so in that case, make sure you buy the couplings kit from toyota, not anywhere else... the toyota couplings are the best and only works for 94-99 taragos
I'm thinking it's the aftermarket flex couplers installed on a used shaft. It could be either shaft, but I'm guessing it's a 91 - 93 (more of those out there for cores). You'd probably be better off to finding a used 94 & up shaft, then purchasing new couplers from Toyota. Tim