Why my tire pressure ALWAYS GO LOW?
 

Mine is 2007 TCH with 38K miles. I replaced all 4 tires back in AUG 2012 when my mileage was about 25k I think.

The Tires I bought brand new and installed were 215/60R-16 Bridgestone Turanza serenity Plus.

I drive only about 30 miles a week. Since the last 8 months, I get the low pressure warning signal ( the crown orange icon) and I check with my digital tire pressure tool and I see it go down from 34 to 29. I put air in , drive and the warning sign goes away but after a week, I get the warning again and same thing over and over. I am sick and tired of it. Not all tires but always one of the tire goes low on pressure every week. Again, I drive only about 30 miles a week.

What can be wrong?:(
Thanks

Re: Why my tire pressure ALWAYS GO LOW?
 

It is possible that the tire was not properly installed, and did not get an adequate bead on the wheel. It is also possible that the valve stem is defective, or not tightly screwed in. And it is possible that you have a defective tire. The tire installer should be able to determine the problem pretty quickly if the leak is large enough. They can apply a soapy water over the tire and look for bubbles, and may have other ways of finding a leak.

Re: Why my tire pressure ALWAYS GO LOW?
 

Mine was installed brand new in 2012 and had ZERO trouble except for couple of nail issue but the air leakge or low pressure started happening since middle of last year. I get low pressure warning almost every 30 miles. It is not on same tire all the time. What should I do and where should I go?
I don't want to go to the rip off toyota dealer for check up because they always give you laundry list of repair even when my car was like 10k miles.

I know an independent auto repair shop. Go there and tell them I lose tire pressure very frequently and ask to check what could be wrong?

Thanks

Re: Why my tire pressure ALWAYS GO LOW?
 

If you have alloys they WILL leak out. Every alloy we ever had does this. Slower, faster, they all do.
The only fix I know of is to take to LSchwab and ask them to REALLY seal it. But I had alloy that had that done four times and it still leaked. Honda alloy. Micro-pores in aluminum, I guess.
Oh, and do NOT ever use rim mounted balance weights on alloys. Adhesive ONLY.

Re: Why my tire pressure ALWAYS GO LOW?
 

Thanks! I didn't understand you but I will check what LSchwab is or where it is. I was thinking about taking it to an independent auto repair/machanic shop to explain to them and fix the issue with regular low tire pressure.

I know there are few tire repair places like JUST TIRES but I heared they rip you off and demand expensive repairs all the time so I am bit uncomfortable going there.

Re: Why my tire pressure ALWAYS GO LOW?
 

What is there not to understand? If you have alloy rims, alloys, they tend to leak air out either at the sealing bead or through micro pores in metal itself. Every alloy we had slowly - or abruptly, usually when night temp drops down fast - leaks air out. Normal fix is to take tire to Les Schwab and have them dismounted and remounted with extra sealant applied. I forgot how much it costs. 20 something bucks I think.
Or, simply get air pump and test pressure regularly.
DO NOT put sealants inside!!! Like FlatFix or similar.

Re: Why my tire pressure ALWAYS GO LOW?
 

Well, no, they don't. I have only owned alloy wheels on my last half dozen cars, and most of those wheels have had ZERO leakage issues. I check my tires every few months (depending on the TPMS perhaps more than I should), and find most of my tires are only down a few PSI in that time frame. I always check before a long trip, and typically will do 3000 miles cross country only to return home without a single tire being different by as much as the 0.5 PSI threshold of my digital gauge.

In case it matters, I do have Discount Tire rotate and balance my tires every 5K miles (less than 2x a year!), and I typically check before and after a visit. I keep my ESh like my TCH before it at 40 PSI all the way around, but DT usually ignores my request and only fills to 35 after a rotation. Point being, DT has never inadequately sealed the tire against the rims, and tire air leakage is not normal for steel or alloy wheels.

Re: Why my tire pressure ALWAYS GO LOW?
 

So they either have ZERO leakage, or they go down a few psi which IS a leak. Small, big, does not matter. A leak is a leak.
You contradict yourself. And if you rotate tires the way you should - every 6 000 miles - that is rather a short period of time for "few psi". I am also presuming, you are either parked inside garage or live in Florida with year long warm climate. This tends to maintain seal on alloy. You go park outside when overnight temp falls from 65 to 32 and let's see what happens. My Ridgeline was notorious about this.

Re: Why my tire pressure ALWAYS GO LOW?
 

Air will leak through the pores in a tire, AND seasonal temperature changes also account for tire pressure changes.

Re: Why my tire pressure ALWAYS GO LOW?
 

All tires have some leakage, steel and alloy, and even inner tubes. I've never know a car or bike tire that did not have very slow leakage. Even with a new valve stem that is tightly seated in excellent condition, there will be slow leakage. This is NOT the leakage the OP was talking about. There is no differences in the very small and very slow leakages that I have seen all tires.