I have been running on 235/40/18 tires in the front for over a year with no problem. However, my tires kept losing pressure since last month. They lost about 5psi per two weeks. Do the tires have something to do with the pressure lost? Or the valves became leaky after 4 years? My car is 07.
Any thought?

 

Could be a crack in the wheel. Take the tire out and check it. It can be dangerous driving around with a cracked wheel.

 

It is odd that it's happening with both fronts. Slow leaks like that can be a real pain to find. At a rate of 5 lbs over two weeks, that's around 1/3 lb a day, so do the math on how little that is per hour or per minute . . . it would be REAL hard to pick that up in a dunk tank, but I guess it's possible if you have some idea where to focus your attention for a VERY tiny bubble. I assume you have thoroughly combed over your tire looking for any penetrations, and it's unlikely that both tires would have identical punctures, so my guess would be either the TPMS seals, or possibly corrosion on the bead seats of your rims. Good luck to you.

 

I don't think there is a crack on both tires. For the time being, I still can live with it since I have a little air compressor to bring the pressure back every two weeks. However, if it gets worse, could a tire shop like Tires Plus or Firestone fix it?

 

they can most likely fix it if they can find it. Also check ur tires to make sure there are no nails or blemishes in the tire. if u drive over a lot of pot holes it can also make ur tires loose pressure.

 

My front left has a similar slow leak but when I stored my car last winter I put all the tires up to 50 psi for the winter. Over the winter all the tires only lost about 3 lbs each and now the front left hasn't leaked since. I'm guessing their was a leak in the bead and the added pressure sealed it up???? Either way yes, if you take your tires in to get remounted they should be able to fix them no problem.

 

I brought my car to a shop for oil change and had them check on the front tires. They said that I am losing pressure because those tires have weather crack. They came to that conclusion without any other inspection other than looking at the tires. They recommend me to change those tires which only have 10k miles on them. Plus, they claim that driving around with those crack tires may cause the tires to blow.
Is it true that tires with weather crack will blow? Also, is my pressure lost caused by tire weather crack? Someone with experience and knowledge of tires please verify this.

Thanks.

 

How old are the tires that are on there?
Have they been severely weathered?
Can you see the cracks that they're talking about?
Can you post close-up pics of the tire cracks?

Kinda need to know a bit more info to give the best answer. Short of that, I'd have to say that unless you've got some really inordinate situation going on with those tires(ie. REALLY cheap, or weathered, or both), it's pretty unlikely that they would "blow" on you. Sounds like the oil change shop is trying to sell you some tires.

 

Slow leaks, unless there is an obvious reason like a visible nail etc, are usually caused by corrosion between two dissimilar materials, such as a rubber tire and an aluminum wheel. I just had both of my rears dismounted, cleaned and remounted. There was considerable buildup of corrosion.

I'm not sure if the quality of the aluminum has anything to do with it but my last two cars (95 Dodge Intrepid..99 300M) I would have to do that process twice a years. This is the first time with this car since I got the new tires.

You can also see evidence of this phenomenon on a car that has aluminum wheels and steel center caps.

By the way, two local tire shops wanted $20 to $25 *per tire* to do this. Nice to have friends in the business.

Mike

 

I brought it to other shop and this shop recommends me to change the seals in the TPMS which makes more sense and cheaper too.
Here is the picture of the weather cracks on my tire.