As far as underappreciated car parts go, the humble lug nut is right up there. These little guys have to hold a wheel on — a pretty critical task — and stand up to multiple wheel swaps throughout a vehicle’s life. It’s a thankless task, only drawn attention to when something goes really wrong, and you’d think that a basic fastener would be simple enough to make correctly, right? However, by cheaping out on making a certain type of lug nuts look good rather than function well, automakers have given consumers one giant pain in the ass.
Over the past few decades, a proliferation of aluminum alloy wheels has led to increased demand for better-looking lug nuts. While there’s something earnest about unadorned wheel fasteners, people like the look of chrome on lug nuts, and chrome is a fairly durable coating. It doesn’t like to rust nearly as much as bare steel, it stands up to power tools well, and there’s an almost corvid appeal to shiny objects.
The problem is that chroming an entire lug nut isn’t the cheapest way to go, and if there’s a way to save a few cents per car, that can add up to millions of dollars in efficiencies over several years. As a result, wheel fastener suppliers came up with the chrome-capped lug nut by taking a standard unadorned steel lug nut and pressing on a thin, decorative chromed cap on each lug nut that’s non-removable. Unlike Volkswagen’s purely ornamental plastic wheel bolt covers, these chromed caps can support the torque of an impact wrench and are permanently fixed to the wheel retaining hardware so they won’t come loose or get lost.
The problem arises when moisture finds its way in between the steel lug nut and chromed cap. Trapped moisture leads to corrosion, and because the cap is relatively thin, the corrosion forces it to expand outward. If it expands far enough, the lug wrench that came with your car to change a tire on the side of the road might not fit, and that’s a real pickle to find yourself in should you get a flat.
In addition, it’s also a pain in the butt for mechanics, not just because the expected socket might not fit, but because the chromed caps can weaken from years of corrosion and peel back like razor-sharp tin foil when hit with an impact wrench. Add in the fact that when chrome-capped lug nuts fail, owners will be on the hook for new hardware, and while that isn’t a huge expense, it’s still an unexpected one.
Seven years ago, Ford was actually sued over the two-piece lug nuts (ones that have a sheetmetal cap over top of the less-pretty nut that actually does the clamping — see this article about how to remove them) the automaker installed on millions of vehicles, with the class-action complaint claiming “The defective nature of Ford’s lug nuts renders the vehicles that they are used on dangerous and unfit for their ordinary purpose of providing safe and reliable transportation.” However, Ford Authority reports that the suit was dismissed in 2019, meaning these lug nuts are still out there causing problems, and owners have little in the way of recourse.
However, it’s not just Ford using two-piece lug nuts. Chrysler also uses them, GM uses them, they’ve been on everything from full-sized trucks to muscle cars to compact sedans, and they’re annoying in every application. A more memorable expression of fury is a Reddit post titled “Has anyone thrown their old lug nuts through the dealership window yet?”, but that’s far from the only case of someone taking to the internet to raise awareness of chrome-clad lug nuts.
Fortunately, there is a solution that’s virtually inevitable — if you have chrome-capped lug nuts, you likely will need to replace them at some point, and when that happens, go for aftermarket one-piece lug nuts. They might be a little bit more expensive but by directly chroming the hardware itself rather than going with a dress-up cap, they won’t ever come apart. We’re talking about a case of “buy once, cry once,” and although more durable single-piece lug nuts should be standard from the factory, the widespread existence of a reasonably priced aftermarket solution makes swollen lug nuts easier to swallow, once the pain of getting them off has subsided.
(Photo credits: Reddit, Hagens Berman)
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I hate these so much I’m considering stopping in a Ford dealership, taking a test drive, negotiating a price and then walking out when I discover the vehicle comes with these abominations. FYI Rock Auto has solid replacements cheap.
I used to work at a Lincoln/Mercury dealer and these things were hell. I would try to avoid putting a 20mm on a 19mm but sometimes that’s the only way to do it. The tried and true method was to gently tap the correct size socket on then give it a couple of good wacks with a Phillips head screwdriver through the socket hole to pop the lug nut back out of the socket. (pro tip-use an old valve cover cap from a tire on the Philips head screw driver so it doesn’t damage the finish)
The Dorman replacements are solid chromed ones and are far superior.
We just replaced all 20 on my brother’s ’18 Regal (well, the remaining 14 we hadn’t replaced) this year because they were getting really sketchy when I’d swap tires in spring and fall. The years it spent in Quebec before he bought it really ruined those.
The Dormans are way nicer and I no longer have to worry about a lug nut potentially turning itself into a circle.
My old car has steelies with steel lug nuts. All of the above – the rims, the nuts, the studs, and the old car – are now rusty, but I haven’t had to replace any of them.
My wife’s Chevy had these plated lug nuts. They weren’t awful but they were frustrating. As long as you use a decent 6pt socket they always come off, but eventually the plating falls off in a single piece. I’d try to pound the plating back on just to make it look pretty.
Guys those are chrome plated lugs, your gonna strip em – Wolverine…
The factory capped nuts are NOT chrome, they are stainless as others have mentioned.
These articles often mention rust jacking as a common cause of failure. Yet the pictures are always of nuts that were murdered by the Ugga-Dugga, the use of 12pt or shallow sockets. This one is no different. I’d love to see some pictures of actual rust jacking caused failures.
They do not stand up to impact use since they are not designed to have an impact used on them.
I’ve got some that are over 20 years old and are still in great condition,
The cheesy lug nuts on my Ram 2500 are a stainless cap on a pot metal base. I think people confuse stainless with chrome a lot since real chrome is pretty much banned for environmental and H&S reasons.
The cap is pressed on the base and water can easily get between them. The pot metal base then rusts and jacks the cap. I was very careful to crack each one with a long socket rather than use an impact on them (although it’s pretty stupid to expect people to not use an impact on wheel nuts).
I started by replacing them one at a time when they started rusting ($10 each from Ram). Eventually, I gave up and replaced all 32 of them with the Dorman one piece replacement – I think this is the first time that Dorman has actually made a better part than the factory. I haven’t had any issues since.
I understand that rust jacking can and does occur, I just find it annoying that all the articles talk about it, but never show pictures of nuts that actually have that problem.
And yes I agree that it is a pretty bad idea to have lug nuts that aren’t designed to be used with an impact wrench when you know that is the commonly used method to remove them.
Yea I worked at a dealer on flat rate. When you are trying to turn cars over as quickly as possible you are not using a breaker bar to pull off 20 lug nuts and then checking the torque with a torque wrench. Its all impact on and off. I used bluepoint torque sticks 100lb-ft for the Panther platform stuff, 147 lb-ft for the F150’s and light duty trucks, and whatever the owners manual called for for anything else. People at dealerships and service places don’t have time to use hand tools.
At my work, we spent many years tapping threads through those two-piece Ford lug nuts. The volumes were crazy high, probably because they constantly had to be replaced. Environmental regulations between the 1980s to 2000s took all of the best and very poisonous plating options off the table – No more cadium, no more hexavalent chromium (I think those were used on these nuts?). I’m sure there is an environmentally friendly option they could’ve used, but hey, that would’ve likely cost $1 more per car, so here we are.
Just in case, there are a couple of manufacturers of six-point half millimeter size flip impact sockets out there.
The “+.5” side is for the rust swollen cap and the flip side “-.5” is for the caps that have torn/already fallen off. They’ve saved many a rust belt mechanic a ton of misery
One of those manufacturers is JS Products under their Steelman brand; they make a 18.5/19.5, a 21/21.5, and a 22/22.5 and they get a TON of use at work!
I put new lug nuts on my Tracker 2 years ago. They were relatively cheap, but seemed to be decent quality. Nearly each one of them has this plating peeling off now. In TWO YEARS. Where I live really doesn’t get a whole lot of snow, therefore not a whole lot of salt. Unacceptable. Now I’m trying to find some black oxide/galvanized or something as an alternative. It’s a beat to shit Chevy Tracker, I certainly don’t need pretty lugnuts.
FYI, black oxide does not have any real effect for corrosion.
McGard toughnuts hold up well in the salt and aren’t stupid expensive.
Good to know!
Also once said chrome cover comes off, your factory supplied socket/wrench no longer works. As I found out at 2am in the middle of nowhere south Dakota. Finally got it by putting the cover on and hitting the wrench till it smashed it all on tight enough to get it off.
These nuts are terrible, and I tend to replace them anytime I see them, but they are not the problem so many people make them out to be.
I see people have issues with the at the shop all the time, and it always comes down to 3 key factors:
Every time I have to help somebody with these, or we have to order replacements so they can finish the job, it ends up being one of these three or some combination of them.
It’s also easy to deal with them when damaged.
I keep a selection of cheap 12-point impact sockets on hand. I hammer on the one that does not quite fit, and it comes off every time.
I absolutely hate these nuts, but I agree that people tend to make them worse through poor treatment (or at least from the tire shops they bring their cars to). The other thing is that they often don’t bloat like the triceratops from Zelda overnight, so unless your wheels stay on for years without even being rotated, you’ll probably get a warning when the socket gives a little trouble going on (and coming off) before it gets to the point of “murder is the case that they gave me” and they can be changed out then instead of waiting. I don’t have these lug nuts, but it’s another reason I prefer to swap on my alternate wheel set and drop the ones needing tires off at the tire shop to have them swap them out as I know that way that they’ll be torqued properly by hand when I put them back on.
just replaced mine, 2006 Acura MDX.. old ones were swelling and cracking.
$26 from Rockauto for the set.
These lug nuts are the reason I own an air chisel.
For pressing off studs? I don’t see any other way an air chisel would help. I use the stripped socket tool that cuts into the lug nut when they are completely gone. You hammer it on and use it like a regular socket. I’ve never had an issue with getting one out. Now, getting the damaged lug nut out of the tool is a whole other issue lol.
The outer shell was completely rounded off and basically fused to the nut underneath so used an air chisel to break the shell so I could get to the actual nut underneath.
You should probably have described what a 2-piece lug nut is and why they are used. They consist of two pieces of metal that are attached so they can rotate around each other. The base is tapered to match the wheel holes and help center it. The top has the threads and is used to torque it down. They are great for soft aluminum wheels because the taper does not rotate against the wheel which allows more accurate torqueing and does not gall the surface. I personally like them a lot but they need to be kept clean and replaced occasionally, especially if you have a lot of snow and salt.
A good point. I would add that the base can be tapered or flat.