What is the catalytic converter monolith ?
The monolith is the part of a catalytic converter that reduces the levels of
pollution produced by an internal combustion engine. You cannot see the monolith as it
is fitted inside the main body of the catalytic converter.
What is the difference between a ceramic and steel monolith ?
Steel monoliths are more durable than ceramic. A steel monolith will last longer than a ceramic one.
In addition as ceramic materials are more brittle than steel,
the steel monolith is more likely to survive impact damage from grounding than ceramic.
However impact damage can destroy either type and is excluded from both our and other suppliers warranties.
What is best choice for me ?
Diesel cats are fitted with a steel monolith as standard.
For petrol engined vehicles the choice is largely a financial one. Either type will last far longer than the
warranty period under normal conditions. A steel monolith may survive impact damage that would destroy a more
brittle ceramic monolith. To make your choice you should compare the price of the part, fitting kit and fitting
cost against the improved warranty period and consider how long you are likely to retain the vehicle.
Where your original cat has required replacing prematurely because of a loose, rattling cat, particularly common in
the case of Mercedes, I recommend replacement with the superior steel monolith.
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