My tyres are losing pressure - why?

My daughter has a Mazda Bongo fitted with steel wheels, on which are Wanli 195-70-R15C tyres.

For about a month, one front tyre has been deflating. It takes about four days to lose half pressure. This morning she found that a rear tyre had deflated, with no obvious cause. The front was recently checked by Kwikfit, who could not find any cause for the deflation, but fitted a new valve "just in case" free of charge.

I have seen that Wanli is a cheap Chinese make, and I suspect that these tyres were fitted to improve the vehicle dealer's profit when the Bongo was sold to my daughter three-years-ago.

Do you have any information on this make, and the deflation problem? I am aware that alloy wheels can seep air, but have not heard of steels leaking.

Asked on 31 May 2013 by grandadstaxi

Answered by Honest John
Never heard of them. But then I close my ears to all cheap tyres. I suspect the rimseals have failed. Might be possible to re-seal the tyres to the rims, but better to fit a proper set of tyres. A sudden deflation on the motorway could cause a fatal crash in a high sided vehicle like a Bongo.
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