In extended technicolor (ETC) theories, while the sideways ETC boson exchange decreases the width Γ_b ≡Γ (Z→ b b̅), the flavor-diagonal ETC boson exchange tends to increase it, and the ETC-corrected R_b ≡Γ_b / Γ_ had value could agree with recent measurements. The τ asymmetry parameter may also increase in a way consistent with experiment. The weak-interaction ρ parameter receives a correction from diagonal ETC exchange which is just barely acceptable by experiments.