Search for a 4th generation up-like Quark at CDF

We present a searches for a massive quark (t') decaying to Wq and separately Wb, in data collected by the CDF Run II detector corresponding to 5.6 fb$^{-1}$. We use the reconstructed mass of the t' quark and the scalar sum of the transverse energies in the event to discriminate the t' signature from Standard Model processes, and set limits on the mass of the t' in these new physics models.