Astra catalytic converter part number

Hi all, does any know the part number for a genuine Vauxhall cat, the one that starts with GM?
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Senior Member
All GM part numbers are 8 digits and are usually stamped/embossed on the part itself.

If you want a genuine GM catalytic converter it's part of the front pipe assembly and is exchange only.

Astra G - Z22SE [L61] Engine (Hatch,Saloon,Coupé,Estate,Van,Monocab) (F07,F08,F35,F48,F69,F70,F75):
Part # 55558954 - Pipe Assy,Exhaust,Front, with Catalyst; New Exchange (Core Return No. 9117104)

Brand new genuine ones appear to be very rare, a Vauxhall dealer may have one but I'd imagine it would be expensive.

Hope that helps :)


Senior Member
Forgot to mention that the Genuine GM downpipes have the pre-cat installed whereas some of the aftermarket ones don't.

Some aftermarket alternatives:

BM Catalysts - part # BM90839
Klarius - part # 321503
Walker - part # 20873