A subframe sits in the vehicles chassis and works in conjunction with the cross member to house the engine and steering components. It also helps to spread the load over a wider area.
Due its location positioned under the vehicle, it can suffer damage from impact or a collision causing it to bend. It is also prone to rust over time.
If you are experiencing issues with your subframe, check to make sure it is not the subframe bushes or misalignment is not the issue caused by a loose fixing. If you still require a replacement, the suframe can be easily replaced at low cost but it is advisable to use a qualified mechanic.