We have blogged before about the challenges of handling a wreck involving an 18 wheeler. If you are involved in a serious wreck with an 18 Wheeler, be aware that it is very likely they will have experts, including accident reconstructionists, on the scene within hours. You should not delay in seeking help. You need someone preserving evidence on your behalf and making sure that everyone involved will be treated fairly and justly.
Most 18 Wheelers have downloadable data in them that should be preserved after a significant wreck. The data can show braking, speed, rpms, steering input and numerous other pre-crash items important to reconstructing what happened. This information needs to be preserved for all parties involved.