The Mountain Goat, which is based on one of the original chassis from 1895, was delivered to Gwynedd from Derbyshire where it was built.
It follows the Snowdon Lily, a similar carriage which was introduced in 2013.
The Mountain Goat arrived at Llanberis station on Wednesday morning.
A new £150,000 steam carriage has been lifted into place by crane at Snowdon Mountain Railway.