Wheel spacers and the Hub-centric vs Lug-centric debate

[Neto]

Because I'm in a situation where (for our family car - winter wheels and tires) I'm considering something I never thought I would look at twice, I've been trying to get to the bottom of the question of wheel spacers.

I did a search here for information, as well as a couple of other forums about the wisdom of using wheel spacers. I did find one comment here from Torchie, who said that he has never cared for them. (Not his exact words; I read that a couple of days ago.)

An article on Summit Racing came up in the search, and I thought that perhaps quoting most of it would be a good start, to demonstrate the two sides in this dispute.

[URL="https://www.onallcylinders.com/2016/07/28/hub-centric-hubbub-argument-using-hub-centric-rings-wheels/#:~:text=If%20you%20don't%20use%20hub%20centric%20rings%2C%20you%20transfer,mounting%20surface%20on%20the%20axle."[/URL]

Hub Centric Hubbub: The Argument For — and Against — Using Hub Centric Rings with Your Wheels
David Fuller - OnAllCylinders' managing editor

Depending on who you believe, hub centric rings are either: A) essential to the performance and longevity of your wheels, or B) a scam created by the wheel industry to charge the customer more money.

As usual, the truth lies somewhere in between.

A hub centric ring is used to help a wheel stay centered during installation. It fits over the center bore of the wheel and over the hub pilot on the axle, filling up the space between the two surfaces. Most aftermarket wheels are non hub centric, which means the center bore is intentionally made larger to fit over a variety of different-sized hub pilots. For this reason, Summit Racing recommends the use of hub centric rings with all its aftermarket aluminum wheels.

According to the Summit Racing tech guys, you shouldn’t use hub centric rings in these cases:

Factory wheels: these are made for a specific vehicle and are made with an exact center bore diameter to fit that vehicle’s hub pilot diameter — no rings needed!
Steel wheels: these wheels have a thinner mounting surface and are often too thin to accept hub centric rings.
Any wheel that uses a push-through center cap as they will not accept hub centric rings.
Any wheel with an “as cast” (non-machined) center bore, like the Cragar S/S, will not accept hub centric rings.
There are also a couple of myths involving hub centric rings.

The first myth is that if you don’t use a hub centric ring, the wheel will never be centered on the axle, leading to uncomfortable wheel vibrations while driving. While it is more likely that the wheel will be off center without the use of hub centric rings, it is not impossible to center the wheel by following proper installation technique. However, Summit Racing recommends the use of hub centric rings to improve the ride quality of the wheel. The rings improve ride quality by holding the wheel centered while it is torqued down.

According to a second common myth, the weight of the vehicle is supported by the hub pilot mating with the center bore of the wheel. If you don’t use hub centric rings, you transfer the weight of the vehicle to the lug hardware, and the wheel studs will break.

Fact is, the hub centric rings do not bear a load. The weight of the vehicle is actually supported by the friction between the wheel and its mounting surface on the axle. The friction is established and maintained once the lug hardware is properly installed and torqued to specs.

Hopefully, you now have a better idea whether you need hub centric rings for your setup. If you’re considering purchasing a set for your wheels, here are some buying tips from the Summit Racing tech guys:

Plastic hub centric rings are best for street cars in areas where rain, snow, and road salt are a concern.
Metal rings are better for race cars and other vehicles that get driven harder, creating more heat.
You will need to know the inner diameter of the center bore on the wheel and the outer diameter of the hub pilot on the vehicle.
Center bore diameter is listed on the Summit Racing website.
Check the size of the hub pilot on each hub (front and rear, left and right). For several reasons, the sizes may vary on the same vehicle.

Next, I'll post a response which is in the Comments Section after this article. (It was too long to put it all in one post.)

 

[Neto]

A RESPONSE (in the comment on the article above):
A Response from Yasenia, who presents the other perspective.
[This was really long, so in addition to deleting some foul talk, I also made spelling and grammar corrections, and summarized some sections.]

I, and automotive engineers I know or have talk to, disagree with Mike.

[Some people say] that hubs do not carry any loads, that the wheels are held in place by the friction created by the lugs.

In my research [I consulted with] the engineering dept at Katana Wheels, who stated:

“The other element that affects directly whether a wheel can be bolted onto a car is hubcentricity. Long ago, wheels were located by taper of the lug nuts or bolts. This could lead to all sorts of problems, but they can be summarized by saying centering was liable to be less than perfect, and the sheer stress on wheel bolts or studs could be enormous. We are not aware of any passenger car wheels now made that are not hubcentric.

Hubcentric wheels have a

hole that fits closely over the hub, serving to center the wheel on the axis of the spindle, as well as bear the vertical weight of the vehicle. The wheel bolts or studs then serve simply to hold the wheel onto the hub, and are loaded only in tension, where they are strong. If the studs were required to absorb vertical forces, they would be loaded in single shear, the weakest arrangement for any fastener. Factory wheels are all machined to fit their specific application exactly.”

[Considering the technical properties of] fasteners, such as the metallurgical properties of fasteners and their design, [this] makes more sense than [the idea that] hub-centric wheels do not carry the load.

Tightening the lugs at 80-100 ft-lbs. would not generate sufficient friction to prevent any lateral movement of the wheel from the center of the hub horizontal axis if at highway speeds one were to encounter anything larger than a small crest or other imperfections on the road surface, extremely hard braking, and so on. Or even a larger pothole at lower city street speeds could create enough force to give you trouble. And that is only putting the weight of the vehicle at 2,000 lbs.

This is especially true if using low profile tires. Automotive designers take into account the Free Radius, Static Load Radius, Deflection, Section Height, and so on when designing suspension systems. That is because tires are part of the suspension system. A tire with a higher Section Height (“profile”) absorb more road “shock” and gives you a smoother ride than a low profile tire. That is basic knowledge.

I am not saying that whatever friction generated by the tightening of the lug nuts doesn’t help, but to say that [friction] is the only factor preventing vertical movement would [also be incorrect].

I started suspecting this when I put new wheels and tires on my 2017 Honda Civic. They installed centric rings but they were made of polymer. At first there was no problem with the car, but later I started to feel vibrations in the gas pedal and steering wheel.

Fujita [apparently someone in a Japanese auto manufacturing operation] said that he’d talked to a couple of guys from the suspension engineering dept. at GM. They told him that YES, the hub DOES carry loads.

They added that they had discovered that lugs were failing in part due to lateral load sheering. Many [? Engineers? People in general?] attributed this solely to over torqueing the lug nuts, but it was discovered that this was only part of the problem. You can actually tell what went wrong with the lugs by examining where and how they broke under a microscope or through other none destructive testing. So manufactures switched to hub-centric wheels to help ease the lateral sheer off the lugs, among other benefits.

This makes sense to me base on my research and after noticing what I refer to as “compression load damage” on polymer centering rings.

[Elongation of ] the lug holes on a wheel. [is evidence that the wheels move in relation to the hub due to] the stress imposed on the wheels by road loads.

Charles C. Roberts Jr, PH.D, P.E., (an engineering consultant in the areas of accident reconstruction, failure analysis, structural analysis, heat transfer, fire origin analysis, computer analysis, mechanics, and biomechanics) puts it this way.

“It should be noted that hub-centric and lug-centric wheels are distinct designs with different stress levels at different locations. Substituting a lug-centric wheel in place of a hub-centric wheel can decrease reliability, especially in high wheel-loading and impact-loading environments.”

If the center bore diameter of the lug-centric wheel is too large for the hub, that the same as a hub-centric wheel with a bore that is too large for the hub. Neither one will fit snug around the hub, meaning that lateral movement could be possible.

I invited a friend who is a thermal and mechanical engineer to go with me to an area auto dismantling center. We looked at after market wheels and discovered that some had signs of wear similar to that which one would find in a lug-centric wheel installed on a hub-centric setting. We looked for any hub-centric rings still installed on the wheels or marks that some had been installed previously, but on the wheels with the oval wear [in the lug holes] none were present.

I also called Versus Racing, asking about the ins and outs of hub-centric wheels and their thoughts on hub centric rings. They said that “the hub IS a load bearing component…”

Based on the answers I got from engineers/designers and the tell tale signs left behind on the used wheels we inspected, I would have to disagree with the idea that hub-centric wheels do [she seems to have missed inserting the word ‘not’ here] put loads on the hub.​

 

[Neto]

I noticed that Mike (the author) was talking about hub-centric rings, and whether they are necessary, and the person who made the response I posted above in summary form kind of misrepresent him to some extent, because she was talking about hub-centric WHEELS.

Anyway, I think that they both are uninformed regarding how older vehicles were designed in this subject area. My 46 Plymouth is an example. The wheels fit very snugly on the very substantial hubs, both front and rear. I have always thought that the hub bears the weight of the vehicle, in respect to its connection to the wheel. Certainly the lug nuts (bolts in the case of the old MoPars) must be present to keep the wheel in place, but I always assumed that their function was just to hold the wheel in place. So certainly they would bear lateral stress, but not vertical (in my thinking). I have a open box trailer (4 x 8) on which the wheels do not engage the hub's outer surface at all (as far as the wheel's center hole is concerned). It is telling that the lugs are larger diameter than any I have ever seen on a passenger car. To me, because they are weight bearing.

So now that I've had my say, I'd like to hear what you all think about this. The primary reason for my interest in this is because we recently bought a 2019 Honda CR-V, and I have not been able to find ANY steel wheels which are indicated for this vehicle. (It has 18x7.5 ET 4.5 alloys on it, and I wanted to use a 17" steel wheel.) Not finding any steel wheels, I purchased a set of used Honda OEM wheels. But there is interference between the inside of the wheel face and the caliper bracket. About a 1/4". My son-in-law found a source for 20mm spacers, but they are too thin to allow for a hub-centric flange, which would set inside the wheels center bore. I had heard of wheel spacers before, but never thought I would consider using them - just didn't seem like a good idea to me.

 

[Bamamav]

In severe operating conditions, racing or hauling heavy loads, I could see where a hub centric wheel would be better, but in the world, there have been millions of lug centric wheels ran millions of miles without problems. Don't think I've ever seen a hub centric aftermarket wheel unless it was a copy of a factory design.

As to spacers, yes, thicker spaces will move that load away from the hub a bit. Will that matter, maybe, maybe not. As long as you have full thread engagement on the stud by the lug nut, a small spacer, I'd say not over 1/4" , shouldn't make any difference. Adapters work the same way, you bolt them to the hub, then the wheel bolts to the adapter. I'm running 1" thick I believe adapters to go from a 5x5.5 pattern to a 5x4.5 pattern on my front . I haven't noticed any problems with them in the 5-6 years I have ran them, with two different wheel-tire combinations.

As light as that Honda is, as long as you don't go overboard with thick spacers and have enough thread engagement on the lug bolts, I would think it will be fine.

 

[offroadrolls]

I've always understood it as an either / or type of deal. A lot of my daily drivers over the years have been German cars, Audi's and the like. They are hub centric. I learned this several years ago on a 2008 S6. I'd purchased a set of take off rims from a 2011 S5 to mount snow tires on for the winter. Even though they were computer balanced the vibration when mounted on the car was pretty bad. Finally, I realized the center hole in the S5 rims were larger than the S6 rims so,they didn't fit the hub tight. I turned out a set of aluminum centering rings on the lathe to make up the difference. Bingo, the vibration was completely eliminated.
So, it seems to me that it comes down to how well the lugs are centered on the hub. Audi's, not so much, they use the hub center to center the rim upon the spindle. I don't know of any cars other than German that run hub centric. As far as strength goes, I would think it would be best to have everything on center and the rim tight fit on the hub.

 

[Old Iron]

The domestic S10 runs a hub centric. Some are almost impossible to get off without destroying the wheel because of corrosion.
I've ran 3" spacers on the rear and 1.5 to 2" on the front of almost every S10 frame swap I've built without any failures. The spacers I use are hub centric also.
A couple of them have had some hard launches which I squinted my eyes thinking there might be a problem but nothing has went wrong yet.
Do I like too use spacers? Heck no, I would prefer to get the correct width rear end or narrow one to fit the vehicle.

 

[05snopro440]

At that point it wouldn't make sense to me to continue on the quest to run 17's, when you're having to run spacers just to get the wheels to clear. I've learned my lesson in the past that I'll do what's needed on custom vehicles to make everything fit the way I want, but on a daily driver I want simplicity and reliability.

If you put on spacers, will they fit with your spare tire?

Sometimes the simplest solution (keep a stock wheel and tire size) makes sense. I run 22's from an Escalade for the winter on my Avalanche with Blizzaks. They're factory wheels, so even though the wheels are an upsize from the 20's, GM used that tire and wheel on the Escalade EXT without issue, so it's perfect on mine. You're trying to reinvent the wheel (literally) on a vehicle whose greatest value is reliability.

 

[Neto]

At that point it wouldn't make sense to me to continue on the quest to run 17's, when you're having to run spacers just to get the wheels to clear. I've learned my lesson in the past that I'll do what's needed on custom vehicles to make everything fit the way I want, but on a daily driver I want simplicity and reliability.

If you put on spacers, will they fit with your spare tire?

Sometimes the simplest solution (keep a stock wheel and tire size) makes sense. I run 22's from an Escalade for the winter on my Avalanche with Blizzaks. They're factory wheels, so even though the wheels are an upsize from the 20's, GM used that tire and wheel on the Escalade EXT without issue, so it's perfect on mine. You're trying to reinvent the wheel (literally) on a vehicle whose greatest value is reliability.

I'm looking at two options for 17" wheels. The more expensive route means using a steel wheel with an additional 1" back space, then use a 1" hub-centric spacer, one with its own lug bolts in the spaces between the hub lug bolts. That would put the wheel spacing back at OEM specs. The spare would sit 1" farther out, but with such a narrow tire, and for a short distance and at low speed, I cannot see that there would be any issues with that.

The other option would be to use the older model (which, I don't know yet) Honda alloy wheels I already bought (thinking that they would fit). This option would require using 1/4" spacers. The disadvantage I see, and the reason for this thread, is that those spacers push the contact point out far enough that the hub flange no longer engages the center bore of the wheel, and yet are so thin that they cannot include a hub-centric flange. I need to go back and verify that these (5 mm) spacers would allow for full thread contact between the lug bolts & nuts.

EDIT: In this last case, I would pull the spacers off when using the summer tires, or the spare. Also corrected the metric dimension of the thin spacers.

If I buy 18" Blizzaks, then I'll just have to have the tires swapped back & forth two times a year. (I have not been able to find ANY 18" steel wheels that would fit the 2019 Honda CR-V.)

Thanks to all for your responses.

 

[05snopro440]

On my local classifieds there's are a ton of winter tire and wheel packages for a 2017 and up CRV. Some steel and some aluminum. Some form of wheel for the car has to be out there.

 

[offroadrolls]

The domestic S10 runs a hub centric. Some are almost impossible to get off without destroying the wheel because of corrosion.
I've ran 3" spacers on the rear and 1.5 to 2" on the front of almost every S10 frame swap I've built without any failures. The spacers I use are hub centric also.
A couple of them have had some hard launches which I squinted my eyes thinking there might be a problem but nothing has went wrong yet.
Do I like too use spacers? Heck no, I would prefer to get the correct width rear end or narrow one to fit the vehicle.

I'd be curious if the wheel would spin true if you ran a rim with a bigger center hole than the hub center.

I've been working on a Frankenstein Suzuki Samurai that may have some issues when I finish and drive it. It's running Toyota mini truck axles with a 6 on 5.5 lug pattern, same as a 6 lug Chevy truck. A lot of the cool kids in the 4x4 world run 17" steelies like the attached picture. I wanted to be cool too so I went on a quest for some 17" steelies. They're common as spare tire rims on newer Toyota Tacoma's and the like. They're also really hard to find and when you do, they're 80 buck a piece. So I came across a set of 4 17" steelies off a 2000 something Chevy Trailblazer for 50 bucks all in. Well, the offset was wrong and the center hole was too small. So, I bored the center hole to 4" and mounted them with 1" spacers so they'd clear the hub and the tie rod end. After reading this thread no doubt I'm headed for trouble.

Next, I have a friend that runs and old Jeep YJ with a rear axle out of an Explorer. He uses spacers for a wider stance. Because he has a locking differential the nuts securing the spacers were always working loose on the trail. After replacing all the bearings, seals and brake components, he torqued them down and welded the nuts to the studs.

 

[Old Iron]

I think I'd have used lock-tite on them way before I'd have welded them.

 

[offroadrolls]

I think I'd have used lock-tite on them way before I'd have welded them.

He did. It would still loosen them up, it just took longer. Welding them was only practical because it's a trail rig and doesn't get driven but maybe 1000 miles per year at the most.

 

[Neto]

On my local classifieds there's are a ton of winter tire and wheel packages for a 2017 and up CRV. Some steel and some aluminum. Some form of wheel for the car has to be out there.

The 2017 was also a 5th Gen CRV, but apparently there were some changes, because when I run a search for 2017 on places like TireRack & Summit Racing, I get some options. But run it on 2018 or 2019, then I get nothing. (Well, I did actually get one that said it would fit, but the offset was different as well as the hub center bore.)
I should have done this long ago, but come Monday I'll pop off an email to the Honda salesman. He was really knowledgeable about the car, and no high pressure, either. He was a pleasure to do business with. [Edit to add: Instead of doing a test drive myself, we had him take us for a ride. The whole time was a "tutorial", as he went though one feature after another. Yeah, my head was spinning by the time he got back to the dealership, but some of it actually stuck.]

Regarding this general topic, looking at the meager (thin) rim of the "hub center", I was ready to conclude that it's only purpose from the Honda engineers' perspective was to center the wheel before torquing the lugs. But if you do it the old tried & true way (pick clockwise or counter clockwise and go around every other one, just snug them up, the continue going around tightening each one incrementally), then the wheel gets centered automatically, by the shape of the lug nut (or bolt, on many older cars).

The lip on the hub of our CR-V is very thin at the edge, and then it's actually cut back thinner yet closer to the main part of the hub. (Contrast that with the hub on a car like my 46 Plymouth....)

 

[Neto]

In case there is any interest, an update:
The Honda salesman suggested checking with a Honda technician, but I have no idea how to contact one. So I ordered a pair of 5mm wheel spacers. They came almost 2 weeks ago, but it took a bit over a week before I had an opportunity to test fit the wheel. It clears, although not by a great deal.
The stock wheels are 7.5x18, and the used wheels I got are 7x17. So, I have trouble wrapping my head around this. The offset on both sets of wheels is the same. The winter wheels are 1/2" narrower, but I'm pushing the fronts out 1/4". So where does that put the centerline of the tire on the snows in relation to the stock tires? Is it 1/8" out from stock? But how does the narrower wheel affect this? (Can you tell I'm not good at math?)