What you talking about Willis? Carpet guard liners? What happens when you run over a muddy puddle?
The Euros have had these type of liners for years to help deaden the sound of tyre/road noise in the cabin.
The only thing I've always thought is strange is the Euros have it on the rear where the wheels are under the back seat but not in the front where the wheels are adjacent to the engine bay.
The Commodore is the opposite and has them at the front and the material used in the Euros is much thicker than the material used for the Commodores.
Whenever I buy a new car that has this type of material as an inner guard liner, the first thing I do is remove the wheels, make sure the liner is clean and if necessary use a mild carpet cleaner, let it dry then add 3 coats of Scotch Guard allowing time for each coat to dry.
It takes a day or so to do but it's an easy job.
I find after Scotch Guarding them most of the road dirt and grim just hoses off.
While the wheels are off I also take the time to clean the rims and add a couple of coats of ceramic protection to also make them easier to clean.
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