The official notice
Defect
On certain trucks, the axle housing(s) may not have been manufactured properly. As a result, the axle retaining nuts could loosen and detach. If this happens, the axle shaft(s) could separate from the axle housing(s). This could cause reduced braking and/or reduced vehicle stability. Note: This problem could cause noise, vibration and/or a differential oil leak.
Safety Risk
Reduced braking can cause extended stopping distances. Reduced vehicle stability could cause a loss of control. Both issues could increase the risk of a crash.
Remedy
Toyota will notify owners by mail and advise you to take your truck to a dealership to inspect the rear axle assembly and retighten the axle retaining nuts. If weld spatter is found, it will be removed. Any damaged axle components will be repaired or replaced, as necessary.