Following the FirstGroup's decision to buyout their partner's shares in Great Western Holdings a decision was made to rebrand the Great Western Trains HST units to First Great Western (FGW). Visually this change involved the fitting of a new vinyl gold strip and colour fading as well as fitting new FGW logos. Power car 43136 entered service at the end of November 1979 and was overhauled and fitted with a new MTU engine between February and April 2007. Power car 43189 entered service in May 1982 and received its Brush overhaul between November 2007 and January 2008.

Formation:

• LA33 43017 41131 41132 40736 42271 42196 42272 42273 44033 43189
• Class 43 - 43136
• TGS - 44033
• TS - 42273
• TS - 42272
• TS - 42196
• TS - 42171
• TRFB - 40736
• TF - 41132
• TF - 41131