A slang term used to describe a major upgrade or overhaul to a system or network. A forklift upgrade is considered a large-scale upgrade where large parts of the existing infrastructure must be overhauled. A forklift upgrade requires investing in or buying new hardware, and possibly the hiring or contracting of on-site technicians to complete. In today's world of technology, this term is often used in discussions relating to large-scale businesses and enterprises upgrading their existing PBX telephone system and telephones with a new VoIP system and IP phones.
The term forklift upgrade is not a new term. It actually originated during the time of large mainframe computers, where the only way to upgrade was to remove the old machine and bring a completely new one in on a forklift.