New tires losing air??

Rotus8

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07 MS3
So, I put on new tires two weeks ago, Kumho XS (awesome tires btw). When I mounted them I carefully set the pressures, 33 rear, 35 front. So today I am rolling down the freeway and my TPMS light start flashing. I thought my prevous problem was back, it had been gone since I mounted the tires with a replacemnt set of TPMS sensors. So after the car cools down for a couple of hours I check the pressures and the fronts are at 31, the rears are at 29! All four tires have lost four pounds. Is this something that happens with new tires? Do they relax a bit when they are driven for a while?

I have never seen this before, except decades ago, Goodyear blue-streak racing tires had such thin sidewalls they just leaked a bit. Other than that, I have not experienced this and I have probably gone through hundreds of tires in my driving lifetime. Do I have to check tire pressures every two days? I guess I will for the next few weeks.
 
your rim might be cracked. my tire was leaking air slowly and found out there was a a small crack. just get that checked out. if its all four, it must be a seal issue..
 
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It would be pretty amazing if any kind of sealing leak would be so consistent across all four tires. Tomorrow I will call the guys who mounted them (pro alignment shop who I trust completely) to see what they say.
 
Seems like it's common for the little nuts on the tpms "valve stems" to loosen up. Has happened both times I've done tire changes, one tire the first time and two tires the second time. I suppose it could have happened to all four of yours, though seems unlikely. That's where I'd start though.
 
I'm not surprised. I don't know that particular tire, but I have to check my Azenis every two weeks at a minimum. I just assumed that soft compound tires were more porous or something and decided it was the price you paid for sticky tires.
 
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