Okay, here's a new one?

Yep, I wandered back there and saw him putting air in the tires... I was watching him pretty much the whole time (forgot my book and what the heck else am I gonna do). Also, the tires appeared different and rode different afterwards. I'll be checking my pressure manually shortly.

 

Someone is stealing your air at night. Better go get locking valve stem caps.

 

My tires leak down as well. I lost 5psi in 1000 miles. I have 1600 miles on my lemon. I use a calibrated gauge.

 

have your wives taken out any unusual life insurance policies on you guys?

 

After getting new tires yesterday, they were nowhere near the 34 all around that I requested. When I finally checked them this morning they read from manual gauge.
LF 40 RF 42
LR 38 RR 39
Took them down to 33 all around w manual gauge and the TMPS read the same. All readings were after driving rather than cold.

 

If you have tpms, doesn't it come with nitrogen in your tires? Nitrogen does not fluctuate in pressure by temperature like regular air in your tires.

My 2016 with tpms, steel wheels came with nitrogen. I would check with a digital tire gauage.

 

If those are hot temps, then you will be closer to 30 in the morning.

 

Okay, just verified with hand gauge. Front 27 and 28. Rear 26 and 27. Could my wheels be defective? No idea why this is happening. But I've been driving around all day and - regardless of air temp - not one of them was reported over 28. They were all 31 when I left the dealer on Saturday.

 

The dealer gave you Nitrogen? That's strange, unusual and unnecessary. In a Tacoma, you will never feel the difference in Nitrogen. If anything, that makes life a bit more difficult since now you have to pay a premium to add air to your tires.

 

I'm guessing you don't have a compressor at home. You need to determine how accurate your hand gauge is compared to TPMS. To do that, I recommend you monitor and write down hot vs. cold psi readings on your TPMS and hand gauge.

Go for a 20-30 min drive to heat up your tires, head straight to a known working air pump and fill your tires to 40psi. verify with hand gauge. In the morning check your hand gauge, it should be around 36-37 psi. If its higher, air down to 36 psi. Reset the TPMS system and go for a drive. It should report around 37-38psi, this is because by the time TPMS does a full reset, the tires will already be warm. Drive for 20min and watch the TPMS, all the tires should remain within 1-2 psi of each other. Pull over and verify with your hand gauge. By know, with all the readings your taking with your hand gauge, your psi could be between 34-35psi cold which is a good baseline.

After all this you should be able to determine the difference in Psi readings between your hand gauge and TPMS. Knowing this will put your mind at ease.

IF your tires drop back down below 30 again, then you have a serious problem that needs to be addressed. But always remember, when in doubt, use the hand gauge.

 

Dealer put nitrogen in your tires for free if your tire is low. I didn't ask for it. It came with it.

I thought the same thing, service manager also told me some 2nd gen has nitrogen too.

I suppose it doesn't hurt if you add air to it, but I will try to keep it nitrogen.

 

When I go to my local Costco, I just pull up to the bay doors of the auto center and simply ask them to check my tire pressure. Often times, they just hand me the hose and ask me what specific pressure I would like and they hard set it on their Nitrogen machine.

 

The day I got my truck, my tpms display told me that one of the tires was like 3 psi lower than the others. I asked the service manager to add air. That's when he told me I have nitrogen in mine. The schrader valve cap is chrome with a green tip and no it does not show red if you are low on air.

 

Used to work in a tire shop. If you don't drive a race car or sport bike, you don't need nitrogen. Nitrogen is supposedly better for the sensors because the moisture in regular compressed air can condense and corrode the TPMS sensor and the wheel. I personally have had sensors so corroded that when I tried to take the core out, it snapped.

So I have indeed seen the corrosion, but I wonder if this is more due to water trapped in a shops compressed air lines that gets put in a tire when it's aired up.

I have also seen the valve stem of sensors corrode from people putting fancy valve caps on. If the stem is metal , you want a plastic cap. A lot of the fancy metal caps cause a the corrosion to occur much faster and possibly get stuck on for chemical reasons I never fully understood.

 

My main issue with Nitrogen on my truck is that I know I'll be airing down when I hit the trails. I do not plan on carrying a nitrogen tank to refill them afterwards. Instead I will have an air compressor. Mixing air and nitrogen isn't bad, but it defeats the purpose using nitrogen in the first place. If you have mixed air and nitrogen, getting back to 100% nitrogen will require purging the tires of all the air which can be a hassle.

I'll admit I'm a bit OCD about my tire pressures, this comes from riding sport bikes. I always set my psi cold, which is why I have a small compressor at home. Having to store and hunt down nitrogen is kind of a hassle IMO.

If you have a free source of nitrogen and never air down your tires, by all means have at it.

 

OP, does your TPMS show the same PSI as your independent tire gauge reading?

 

I'm up 3-4 PSI also. It's normal after driving with normal air in tires. I have mine set @29 all around and once driven a couple of miles, they settle at 33ish usually. I live in LA also like the OP. Not sure why yours settle at 26 though. I'd recommend adding air yourself and checking after a few days again.

If your truck sits in the sun, the tire nearest the sun will also have a variance.
Air gremlins like to mess with TPMS systems.....

 

That's pretty low for city driving, I live in LA also and I run no lower than 33 cold. You get better gas mileage running 35-38 hot.

 

I've tried it at 33, I get the same MPG. Tried between two fillups. 19.2 average MPG....all day, everyday....

What are you getting Tacitos?

 

I get 18 in the city, 22 hwy (cruise control). Aside from economy, you do not want to run your tires too low as it will affect tire wear.