Tyre air loss: Second opinion

[SpeedBash]

I was planning on changing my front tyres but they are not as low as I had initially thought and have at least 6 months wear in them if not more.

However, one of them keeps losing air but, upon checking, there does not seem to be a puncture.

Took it to one of these back shop tyre places and the chap removed the tyre and checked it thoroughly but couldn't find any sign of puncture or anything else that could cause the air loss.

He said it's not unusual for this to happen with a tyre and that it is safe to use - I just need to keep an eye on it.

Anyone had a similar experience? Does the above sound correct?

It's been like this for a few weeks now and I haven't had any adverse issue even with the car being driven on the motorway at speed.

[SpeedBash]

marcus85 said:

Did he check the valve and the bead for leaks?

Yes.

[SpeedBash]

HustleRussell said:

The wheel could've gone porous.

Just remembered, hence the double post, when he said this tends to happen he actually said this tends to happen with alloy wheels.

Sound right?