I am unsure how to go about this, what are the steps to upgrade your Network drivers on ESXi 5.5?
Once you have supported network drivers (either as .vib files, or packed in a .zip file) you can either install them using Update Manager (in case you are managing the hosts with vCenter Server), or you can install them manually from the host's command line using e.g. the esxcli software vib update ... command.
André
and here is an article for your reference.
Find compatible drivers : VMware Compatibility Guide: System Search
Steps to install the drivers : VMware KB: Installing async drivers on VMware ESXi 5.0, 5.1, and 5.5
Andre has said it succinctly, first make sure that you have "SUPPORTED" NIC drivers.
personally I do not update any host hardware drivers outside of VMware updates. (firmware is also a moot case too)
the biggest thing here is if your are going to update a particular peice of hardware in your host out side of a standard vSphere upgrade cycle or patch, you must test, test and then test again. you end up in a non-supported configuration if your just upgrade your drivers for the fun of it.