Scenario A Japanese cars are total tat. They are built out of substandard materials in a shoddy manner, makes you winder how they sell them. Its only a matter of time before another country starts making cars that are reliable and long lasting, perhaps it will be the UK's turn, who knows.

Scenario B Your tyre chappy is a total muppet who does not have a clue.

Which are you voteing for?

"Bull excrement" is a good description of the story.

1. ALL alloy wheels use alloy to a certain specification as required by the manufacturer. Almost certainly all alloy material will include some recycled material.

2. Srangely teh world is not full of stories of Japanese cars breaking down - let alone with slow punctures.

3. We have two Japanese cars with alloys- one is >10 years old. No leaks ever.

I don't believe alloy wheels become 'porous' - for that to happen the metal would have to lose some molecular material to create voids. What does happen is surface corrosion at the bead, where pollutants (such as road salt) creep in. That has happened to all four wheels on my Pug 207 not long after fitting new tyres, making it necessary to deflate them, clean the beads and apply new sealant (or lubricant). If the fitter had done that in the first place I don't think the problem would have arisen - it hasn't since.

It can occur round the valve seat too.

Edited by Andrew-T on 20/01/2014 at 18:09