We discuss a model in which the third generation fermions undergo a di
fferent SU(2) weak interaction from the first two generation fermions.
In general, a flavor changing neutral current interaction is expected
at tree level. Constrained by the precision low energy data, the mass
(M(Z') = M(W')) of the heavy gauge bosons is bounded from below to be
about 1.1 TeV for alpha(s) = 0.125 and about 1.3 TeV for alpha(s) = 0
.115, at the 3 sigma level. This model favors a larger R(b) and a smal
ler R(c) as compared with the Standard Model, but it does not explain
the R(c) data. If one takes the R(b) data seriously, then M(Z') is bou
nded, at the 3 sigma level, to be 462 GeV < M(Z') cos phi < 1481 GeV,
where cos phi is the mixing angle between the two SU(2)'s in the model
. Effects predicted for high energy experiments at the Tevatron, LEP14
0, LEP-II, LHC, and future linear colliders are also discussed.