Nitrogen in car tires

[Traction]

Maybe the physic and engineering experts could explain why the biggest loss of tire pressure in the snow states, and is a huge problem that stems from extreme bead seat corrosion?
I'm not an expert in those things, so please explain how extreme temp changes, oxygen, and water have nothing to do with it? Make me feel stupid when you explain it please.

 

[Garak]

Bead corrosion certainly exists. And, if it's more of a problem in snow states, that indicates to me it's not the problem with the fill, but the environment. Nitrogen fill isn't a fix to salted roads.

 

[Traction]

Originally Posted by Garak
Bead corrosion certainly exists. And, if it's more of a problem in snow states, that indicates to me it's not the problem with the fill, but the environment. Nitrogen fill isn't a fix to salted roads.

From my experience I've found out otherwise. I have a set of 16 inch aluminum wheels off of my 02 Camry XE that I have used every winter driven many miles on 3 different Camry's so far. Normally Toyota wheels corrode the bead seats pretty quickly, as I've seen many times. My wheels have been N2 filled for going on 14 winters with no corrosion, or leak down running Bizzak tires. But what do I know? I'll keep using it since I have an unlimited supply.

 

[Garak]

One never knows. My wheels seemed to be much the same regardless what it was filled with. I still want to know how nitrogen helps out when a soapy water lube is used to mount the tire. In my years with the taxis, bead leaks were more of an issue on mounting, rather than when already mounted. If there was corrosion, a wire brush followed by some Tremclad fixed the issue, since they were ordinary, painted steel wheels.

 

[Shannow]

Originally Posted by Traction
Maybe the physic and engineering experts could explain why the biggest loss of tire pressure in the snow states, and is a huge problem that stems from extreme bead seat corrosion?
I'm not an expert in those things, so please explain how extreme temp changes, oxygen, and water have nothing to do with it? Make me feel stupid when you explain it please.


Most sources say (as per Garak's statement) that the corrosion is from the outside in, as outside contaminants work their way in there, scuff off the coating, and lead to corrosion.

https://www.autoserviceprofessional.com/article/92227/gm-corroded-wheel-bead-seat

Quote
A persistent, slow air leak that causes a tire to slowly go flat and resulting illumination of the TPMS warning light may be caused by corrosion on the (non-chrome plated) aluminum wheel bead seat on 2000-2011 GM passenger cars and light-duty trucks, 2003-2009 Hummer H2, 2006-2010 Hummer H3 and 2005-2009 Saab 9-7X.
Abrasive elements may intrude between the tire and wheel at the bead seat area. Due to relative motion between the tire and wheel, this motion may cause abrasive particles to wear the wheel surface. As the wear continues, corrosive media from the environment may cause corrosion of the wheel bead seat, resulting in tire pressure loss.


https://www.motor.com/magazine-summary/trouble-shooter-february-2010/
Quote
Damage to the clearcoating usually occurs in areas where the wheel is exposed to the most friction and stress. Early signs of coating damage may appear around the wheel lug holes. Bubbled or discolored coating areas are a tip-off. Abrasion caused by contact with an impact socket during a wheel removal and installation may have caused the original damage.
Likewise, constant friction between the tire and wheel at the bead area may cause the wheel coating to flake off. Any water, dirt or other material that manages to penetrate this area will only accelerate the process. Damage in this area may be harder to spot because it's normally hidden by the tire. By the time corrosion appears on the face of the wheel near the bead, you can be certain there's plenty of corrosion hiding where you can't see it until the tire is removed.

 

[Garak]

It's interesting to note, take a look at that thread where someone on eBay had that 1980 General Motors truck with no miles and wanting a bajillion dollars for it. Take a look at the pictures of the wheels, link to listing here. Now, of course, given that this vehicle sat for years and wasn't exposed to the same corrosive elements or damage from driving, you can still see a very good representation of what we'd see with the taxis. That was the exact same type of corrosion pattern we'd see on the GM taxis, except the wheels were painted black.

Yes, sometimes wheels would corrode faster than others. I'm sure banging curbs didn't help either, some wheels were finished better than others at the outset, some were newer, and sometimes, stuff just happens.

In general, a great deal of my disdain for nitrogen fill for tires isn't because it has little to no tangible benefit for a consumer over ordinary air. Here in Canada, at least right here, it's only recently trended to one being able to get "free" nitrogen fills. The Infiniti dealer put nitrogen in the current set of tires when they installed them on my Infiniti, without asking, without charging. At one time, everyone was charging $5 to $10 per tire for a nitrogen fill, and refills only if you had bought from the same tire shop in the first place. I also had access to all the trade magazines, and while talking up the purported benefits to the consumer, the biggest benefit they talked up was the ability to upsell nitrogen fill to customers and how, by perceived consumer lock in, customers would return each time they needed a fill. Even with a refill being free, a customer through the door might spend money.

Now, my luck is terrible. The last three sets of tires I've purchased, across from the Audi to the G37, resulted in me somehow running over a nail each time in the first week of my tire ownership. Nitrogen didn't help or hurt that, and I wouldn't have been any more impressed had I spent $5 or $10 to fill that tire in the first place. And, I do have to vary pressure across the year. What gives me 33 cold PSI in 40 C this summer will set my TPMS off in -40.