look on the actual gearbox itself......near to the gear linkage...it should say...the f13 or f15.......mite need a cloth or a wire brush just to get a bit of crap off so u can see properly...and atorch is a gd idea swsell:):wave:

how do i find out?

you could either have a f13cr of a f15cr

ive got a 1.4 16v sport with a x14xe and need a new gearbox, but which 'box have i got? i think its the f13. did vauxhall use the same gear box with all the x14xe's or did they use some different ones in different models. i.e. astra and corsa