It was like 17 degrees yesterday morning and what do you know......flat on the way to work. For the whole time last week, it stayed closer to 30 degrees and the air stayed in my tire. I am so frustrated.

 

-25oC (-13oF) up here, I had one tire the went low a bit...

 

It seems strange that most of these problems seem to come from the front tires. I wonder if the weight on the front of the car combined with ambient temperature increases the frequency of pressure loss. Could be a construction issue with runflats like ours in general. I ended up replacing all my tires with non runflats and different rims last week. It was completely a pain to refill the tires every day.

Maybe it's time for a consumer report on the safety of runflats since a tire that looses pressure on a whim can't be all that safe.

 

I hate runflats.

 

Same issue here, it was a vveerrryyyy sssllloooowww rim leak. Found it at home with soapy water (actually used my children's bubble blowing solution). Swabbed it on the bead, left it a while, and small "beards" of bubbles formed at the rim. Easiest with the wheel off the car since the solution sits there a while instead of running off.

Theory: Cold causes things to shrink (think Seinfeld...). Different materials expand/contract at different rates. Aluminum wheel shrinks, tire bead shrinks at a different rate, apply some stress (like driving on it) and the two will move relative to each other. Runflats with their sturdy bead won't flex as much as non-runflats, but have more rubber to expand/contract, exascerbating the problem (that thar's my College word of the day).

Bead sealer and an experienced race tire shop = no problems.

Bubble solution is fantastic for finding leaks since it "beards up" on small leaks before it evaporates like more watery soap solutions can.

That brake dust theory is crap.

 

I will have to try the bubble solution on the runflat I have that leaks. It's no longer on the car, but it can't hurt to experiment We may be witnessing more than one problem here as well, since my situation was not a slow leak at all, as I would drop between 15-38 pounds of pressure in less than 15 miles of travel or about 15 minutes...all on mostly straight roads, but it could sit for a week and not drop at all. According to my tire guy the rim was not bent or corroded so maybe the tires themselves warp a bit once they are run short distances while flat causing the problem to happen more often once refilled with air. I think the brake dust theory is a bunch of bull as well.

 

I am in no disagreement with the bunked theory. I have been told that it might be a neighborhood kid by one person, and then the other person actually took my tire off and said that it might be the brake dust...what fun.

I have no slow leak either, it is an instant drop, within 10 min.

 

Maybe if brake dust was alowed into the bead area before mounting the tire, but that's why that area is inspected and swabbed (occasoinally with bead sealer) before tire mounting. Should not happen.

Oh - do check the wheels themselves, if they're not cast right they won't be airtight, don't know if that would lead to this fast leak unless there was some serious metal fatigue though...