Is wheel-rim corrosion a real phenomenon?
I recently took my car into the tire shop, a Discount Tires outlet, because it was riding low on one of the tires. They told me that the reason the one tire had deflated was because the wheel-rim had corroded. Then, they found that another rim was showing signs of corrosion as well. They showed me the rims, and I saw that the metal was pitted, but couldn't identify any pits that seemed likely to cause air leakage. They suggested I replace all four rims at once to take advantage of their current sales promotion (buy-3-get-1 or something).
Given that this replacement would cost me ~$300 (and that my automotive intelligence is pre-school level), I called my father to ask his advice. He immediately said that he'd never heard of such a thing and that they were trying to pull a fast one. On his advice, I had them put my spare on and drove away with the intention of getting a second opinion without providing any of this back story. Of course, I haven't the done that for a variety of reasons. The primary ones being that the rim in question is not encased in its tire (so how could I explain that without the back story) and that I'm not sure who to go to.
I've been living in San Diego, CA since 2003, shortly after I bought this car, a used 2000 Toyota Camry. The first five years consisted primarily of street parking in beach communities.
Should I accept my father's 40-odd-year experience of never having to replace rims for this reason despite having lived variously in Michigan (near the lake), in Los Angeles, and in Connecticut and keeping several vehicles well into the 200,000 mile zone?
Or, should I accept the professionals as honest experts trying to help ensure my safety and my vehicle's road worthiness?
Is wheel-rim corrosion a real phenomenon?
What year is the car?
With respect to your dad, corroded rims causing slow leaks was not an uncommon problem some years back. I know yours is a Camry, but Ford in particular had a chronic problem with this. The old casting processes left porosity and even inclusions and occlusions in the metal, and when the coatings/sealers wore off and the corrosion started leak paths would develop.
The problem has pretty much disappeared. I haven't seen it, but my guess is that they're using inverse gravity casting now, a type of lost-wax process far less prone to porosity and inclusions/occlusion. The molten metal fills the mold from the bottom from a fill pipe above the vat's bottom using the weight of the supply in the vat, allowing all the air to exit the top of the mold and contaminants to settle at the vat's bottom rather than enter with the molten metal. The quality of the castings is far higher.
Try doing an internet search for replacement rims. I did one to replace an alloy rim on my car (darned granite curbs) and found direct replacements on the internet for about 1/4 of the price the parts store quoted.
Another good source of like-new rims are the stock 'take offs' the tire stores and new car dealers have when customers go for fancy wheels. There are millions of Camrys out there, so a check with those sources (alosng with Ebay and Craigslist) might get you a bargain.
But I am a little skeptical, it could also be a bad valve stem or corrosion around where the valve stem goes. Is the tire holding air now?
Wheel rim corrosion is not a rare thing and the problem can be exacerbated by the fact that you live in a beachfront community.
This was not much of a problem 40 years ago because most cars then had steel rims.
The majority now are alloy and aluminum/alloy wheels do not stand up under water, especially saltwater, as well as the older steel ones.
Aircraft are made of aluminum for the most part and corrosion is a factor when servicing those also.
Alloy wheel corrosion? Happens all the time.
The son works for a local service center, and he's the main tire/wheel service tech. And he's told me that everytime there's a complaint where the tires aren't holding air pressure, when he pops the bead of the tire off the wheel, there'll be a white cloud of alumunim oxide dust that comes blowing out of the tire. Then he inspects the bead of the wheel, and there will be pitting. When there's pitting occuring in the wheel, there is also the possibility that the wheel has become porous.
But what he does is, he cleans the bead of the wheel, and then he applies a special epoxy for this purpose. Then sands the epoxy to the contour of the bead. Then he remounts the tire and fills it with nitrogen. Then tells the customer to monitor the tire pressure. If the tire stays up, the wheel is fixed. If the tire loses pressure, the wheel is probably porous and requires replacement.
What causes the wheels to pit and become porous? Moisture! The moisture reacts with alloy causing it to oxidize which causes the white powder when the tire is removed. After all the problems he's seen what moisture can do to alloy wheels, he suggests to customers with alloy wheels, especially with expensive/aftermarket ones is, fill them with nitrogen which contains no moisture. Then there will no pitting/porousity problem.
I don't get how the outside part of an alloy can handle years of salt, spray, water, with no problem, but the inside part of the wheel is so easily corroded by the tiny amount of water in the air.
Now that's a very good question!
You have to remember. The moisture, salt, and spray isn't applied to the wheel under pressure on the outside. So these entities just run off the wheel surface without causing damage. But! Take a gas, any gas and put it under pressure, such as water moisture, and apply that gas under pressure in a vessel, and it will seek the path of least resistance to escape. And that path between a tire and wheel is the bead. So that's where the moisture collects and pits the wheel.
Vixen, did they ever show you where the ACTUAL LEAK was?? Did you see the bubbles caused by the leaking air?? Or did they just show you a corroded spot and say "there! Look at this!"
Often, when alloy wheels leak, it is around the valve stem hole. This is fairly easy to clean up and repair. The area where the beads of the tire actually seal, on the inside of the rim, seldom corrode. Take your car to a shop that does not sell new wheels and have them check it out..
The outside doesn't survive with no problem. Visually corroded, esthetically rotted alloy rims on the older cars are quite common up here in NH from the road salt in the winter. The look is really quite bad.
It's real. It happened on my previous car. Cleaning up the bead area fixed the problem.
Now that the wheel is off, you can find the answer yourself. Pump up the tire, spray it with soapy water or dunk it in a swimming pool, and look for bubbles.
I have needed to bring my car 7 times in less than a year to the same tire store due to low tire pressure. Each time they have claimed that its due to rim corrosion and theyve corrected the problem. I understand that rim corrosion is real but does it sound right that it would need it fixed that many times in less than 1 year?
Make/model/year/miles would help. Is it a steel or alloy wheel? What part of the country? Salt in winter?
2009 HONDA CR-V approx 172K. Alloy wheels. I live in the Northeast so a lot of salt in the winter.
I’d get a new set of rims, you might find steel ones for a decent price. That’s if I was going to keep it. If the tires are getting old you can get a set of new tires on new rims, mounted, balanced, and ready to install from tire rack. Check you local tire shops, they may be able to beat the price.
thank you for your suggestions
Perhaps that is your problem.
No, something is amiss there. I had to repair a corroded wheel rim on my truck to fix a slow leak last summer, so that’s an actual problem we car owners have. But I only had to repair it once, no leaks since. I can’t say what the problem is, maybe the corrosion is so severe it can’t be corrected, or they aren’t doing the job correctly. Seems a tire store would know how to do it though, and to rule out the tire as the culprit, so I’m guessing you are looking at needing to buy a new wheel. By “new”, I don’t mean that literally, you should be able to find a used wheel at the local auto recycler place. You may have to buy 2 in order to get a matched set.
That was my guess too.
Perhaps they aren’t using bead lube. Or seating the beads fully. Or perhaps they’re not putting the valve stems in fully. Or they’re pulling the valves through with the force of an angry gorilla.
Something isn’t right. Perhaps another tire shop could determine what.
It remains possible that corrosion is the issue, but that many problems in on year would be enough to make me wonder about the workmanship.
That’s very true. That’s why salt use is prohibited on air bases. The AF also has the benefit of zinc-oxide to fight corrosion, which is banned in the civilian world. Aircraft also undergo rigorous depot inspections routinely for corrosion and/or stress cracks, as well as walk-around inspections before and after every flight. .
I agree with George and mountainbike. Someone is not doing the job properly if it’s been in there 7 times in one year for the same problem.
Any problem should be easily detectable and quite likely noticeable to the naked eye.
I use a product called NoRimRust when I have a tire leaking at the bead. It looks like grease but is lighter. The can I have is at least 35 years old and we used to use it when mounting tractor trailer tires.