Not all 6” subframe systems are compatible with ICON's Toyota Tundra tubular steel upper control arms. Variations in lift kit design will at times yield sub-optimal conditions to properly align a vehicle when an aftermarket lift kit and an ICON tubular upper control arms are installed. ICON recommends the use of our billet upper control arm on subframe lift applications. The added adjustability designed into the billet upper control arms allow for proper alignment on several popular 6” subframe kits. Please call ICON tech support for more details at (951) 689-ICON.