# Why Do We Torque The Lugs So Often?



## Mt.Zion (Mar 6, 2008)

I know this subject has been discussed several times , but why do we torque the lugs so often? Is it because of the pressure the sidewalls put on the rims being twisted so much on turning? I only torque my tv once when I rotate, and it goes several thousand miles more than the ob. I searched this topic but the search tool wasn't working at this time. thanks as usual for all great advice you ob gurus give. Thanks, Ron.


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## johnp (Mar 15, 2004)

I only found the alloy rims to loosen up in the first 100 miles I had to tighten them twice.The steel rims seem to hold the torque a little better. By the time you get the trailer from the dealer it might have over a thousand miles on them.

John


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## battalionchief3 (Jun 27, 2006)

yup thats about it. Torsonial load is very high on campers tires. Ever see a tractor/trailer make a tight turn, the back tire on the inside will turn in a circle, its called scrubbin' the tires and they try to avoid that. It puts a lot of stress on them, espically when loaded with 50,000 lb on them. Same reason trailers have different tires then the vehcile thats pulling them.


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## N7OQ (Jun 10, 2006)

Mt.Zion said:


> I know this subject has been discussed several times , but why do we torque the lugs so often?


So your wheels waon't come off.

My Dad had one come off last fall, the tire passed him and was all over the place luckly no other cars were around or it could have been worse. I asked a Officer at the PD and he says it happens all the time.


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## bradnjess (Mar 25, 2007)

I torque the lug nuts down before each trip and it's amazing, we're into our third year with the OB and I still get a good turn on at least one lug nut on each rim before the wrench clicks. Knowing this I always make it a part of my pre-trip check list.

Brad


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## 3LEES (Feb 18, 2006)

I had a flat two years ago on I-75 coming back from Topsail. I installed the spare and torqued the lugs. As per guidelines, I stopped about 30 miles down the road and checked the torque. EVERY lug needed tightening. I checked again when we got home. All was good.

Checking the torque AND the pressure is _paramount_ each time you hook up, and at least once during a trip. I think lack of pressure was the cause of my flat. I could have checked it 40 miles up the road when we stopped for lunch, but didn't. Thank GOD we were able to pull off to the shoulder without incident.

Dan


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## tdvffjohn (Mar 10, 2005)

No harm I guess in checking as long as they never get over torgued by doing it wrong. I check every spring, rarely during season and that included 8000 miles in 4 weeks 2 years ago. Same routine with both car trailers. Never had a lug get tighter when I have checked. My choice, decision, whichever. Now, air pressure, about 3 times a season.


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## rdvholtwood (Sep 18, 2008)

The first few trips out I torqued them before I pulled out. I noticed the first few times I had to torque them down pretty good. It seems now though, it only takes a little pressure to get the "click" I will always torque the wheels before getting on the road - its my safety net.


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## swanny (Oct 31, 2007)

It's not that hard to do and doesn't take very long. That's one less thing to worry about while movin on down the road.

It's better to know than to wonder.


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## Southpaw (Jul 14, 2008)

Having zero mechanical skills...I'm assuming tightening the lugs nuts with my star wrench is suitable?


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## Camping Fan (Dec 18, 2005)

Southpaw said:


> Having zero mechanical skills...I'm assuming tightening the lugs nuts with my star wrench is suitable?


Actually, you'll want to use a torque wrench instead of a star wrench. The torque wrench allows you to set the pressure that the lug nut will be tightened too, so it's not too loose AND not too tight. Here's a link to a previous discussion about torque wrenches. Clicky thingy


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## dgilmore12 (Mar 31, 2008)

I keep this in my garage to remind me why.










This was off of a pop up we had. I had a flat and changed the tire and never rechecked the lug nuts. About 100 miles later this happened. The entire center of the wheel melted. The lug nuts were welded to the hub. Fortunately no one was hurt and other than the wheel and hub there was no damage.


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## battalionchief3 (Jun 27, 2006)

dgilmore12 said:


> I keep this in my garage to remind me why.
> 
> 
> 
> ...























































































WOW


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## rock hill (Apr 17, 2009)

Camping Fan said:


> Having zero mechanical skills...I'm assuming tightening the lugs nuts with my star wrench is suitable?


Actually, you'll want to use a torque wrench instead of a star wrench. The torque wrench allows you to set the pressure that the lug nut will be tightened too, so it's not too loose AND not too tight. Here's a link to a previous discussion about torque wrenches. Clicky thingy
[/quote]

Is this from Over tightening?


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## arbee (Feb 3, 2005)

What do you torque your lug nuts to? I'm doing 120 ft-lbs.


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## tdvffjohn (Mar 10, 2005)

But, as you said, you changed a flat. The manual clearly states to recheck the lugs after changing a tire after a certain amt of miles. To constantly recheck when no rims have been dismounted is a little different. Its one of those, read everyones thoughts on the matter and decide which course you will take regarding it.


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## dgilmore12 (Mar 31, 2008)

tdvffjohn said:


> But, as you said, you changed a flat. The manual clearly states to recheck the lugs after changing a tire after a certain amt of miles. To constantly recheck when no rims have been dismounted is a little different. Its one of those, read everyones thoughts on the matter and decide which course you will take regarding it.


That's true, it was after a flat. After that experience, I make sure to check before every trip.


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## Carey (Mar 6, 2012)

When I pick up a new trailer from the factory the wheel lugs are just hand tight.. I torque em to 120 lbs with a torque wrench.. I generally check them again within 150 miles.. I doubt most dealers check them after we deliver them..

If you dont use a torque wrench, its pretty easy to crack a stud.. When that happens, that stud will continue to crack and then the nut falls off.. Once that happens the rest of the studs will fail pretty quickly..

Ive lost 2 semi wheels over the years.. Same deal, the guy over torqued and cracked the stud and within 500 miles the rest of the studs cracked and the wheel fell off..

Thankfully, both times I was able to catch it and follow the loose wheel onto the shoulder while using the hub to keep the wheel from flipping over..

I have seen deaths from semi tire/wheels coming off which we would expect..

I do remember coming up on a grizzly wreck once... A boat tire/wheel came off, and went thru the windshield of a car.. There was a 2 year old little girl sitting in a car seat in the rear seat and in the center..

The wheel went thru and killed this little girl.. It was so sad as the parents we perfectly fine.. There was no hope for this little girl.. Made me cry.. She had extreme injuries as you can imagine..

Always put your kids behind you and not in the center of a rear seat.. Stuff faills off cars/trucks all the time.. Its only instinct to miss something to protect yourself, by centering a flying object up to miss you... Sometimes it happens to fast also..

Having your kids placed behind you and your seat helps to protect them from flying debris... Plus if I have to I will always sacrifice myself to protect my kids in these situations..

I once seen a camper wheel come off and get stuck under the camper for a sec. Then it came out and bounced 50 feet in the air missing all of the cars. It bounced right in front of my semi and bounced clear over it.. It was crazy..

Owls and tires kill several truck drivers a year by coming thru the windshield.. I always and still am worried about something like that happening to me..

I say check them at the begining of each season.. If one comes off, its really hard to say what kind of damage it could do, or how many it can kill..

Carey


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## Carey (Mar 6, 2012)

arbee said:


> What do you torque your lug nuts to? I'm doing 120 ft-lbs.


Thats perfect.. Mfr's recommend 120 lbs..

From what I see out here on the highways, few know this, few torque them. Very few ever recheck them. In the summer I see a wheel problem daily with campers.. Many neglect the wheel bearings too.. That makes for a heavier object flying thru the air as the hub is attached to the wheel when they fall off from bearing failures..

lol, I once seen one come off and pass the camper, then hit a bridge guardrail and flip down into a river.. No finding that one... lol I thought to myself, that will teach ya, you yoyo..

Carey


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## Nathan (Jan 2, 2007)

Carey, interesting aside on the seating for children. When we bought our carseats for our DS, we were told the same thing... Behind the driver first because you will try to avoid the accident (Of course that only worked once we went to forward facing because there isn't room for a rearward facing seat behind my driver's seat in most cars







).

As for the torquing of lugs, I have a story. A few years back, I had pulled off at a rest area to torque them up (they had been off recently for a bearing repack). So I get out of the truck, leaving it running with the family in and get out the torque wrench. I'm working on wheel #2 when another rv'er comes up and asks if there is a problem he could help me with. I responded that I was just checking the torque on the lugs and I got the strangest 'why would you do that' look. I thanked him and went on to wheel #3.


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## Sayonara (Jul 23, 2007)

Colorado~DirtBikers said:


> What do you torque your lug nuts to? I'm doing 120 ft-lbs.


Thats perfect.. Mfr's recommend 120 lbs..

Carey
[/quote]

Thats the same for steel and aluminum wheels, right?


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## NJMikeC (Mar 29, 2006)

I have yet to get a good explanation about this. I easily put on an took off 1000's of tires in my life, never lost a one and never used a torque wrench. I can also nearly guarantee you that you never got a torque wrench put on any of the tires on your cars either. The wheels are countersunk and the nuts are chamfered, (spelling???) which increases the contact point and is so designed that they don't backoff and get loose. I can also tell you that I never seen a car loose a wheel other then for a bearing or something like that. Guess others have though. The nuts and lugs are the same for cars, same for trailers. So how is it that cars don't have to be checked?

I'm all ears, educate me but I don't buy the scraping arguement at all, our rear wheels scrape in our cars and trucks albeit with less of a moment arm. With tight lugs the pressure is now on the bearings.


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## CamperAndy (Aug 26, 2004)

Sayonara said:


> What do you torque your lug nuts to? I'm doing 120 ft-lbs.


Thats perfect.. Mfr's recommend 120 lbs..

Carey
[/quote]

Thats the same for steel and aluminum wheels, right?
[/quote]

This is a bit of a grey area, The MAXIMUM torque for 1/2" studs on a Dexter axle is 120 ft/lbs for the AL-KO are the same . Dexter recommends 90 to 120 ft/lbs of torques and AL-KO recommends 90 ft/lbs. Aluminum is typically torqued to about 80 to 90% of steel wheels. So you would expect to torque them to about 80 ft/lbs.

The absolute torque value is not the critical except you should never exceed the max value of the stud. What is critical is that they are ALL the same, at or near the designed torque. If you torque Steel or Aluminum to 90 ft/lbs you will be fine but you need a torque wrench to do this.


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## Nathan (Jan 2, 2007)

NJMikeC said:


> I have yet to get a good explanation about this. I easily put on an took off 1000's of tires in my life, never lost a one and never used a torque wrench. I can also nearly guarantee you that you never got a torque wrench put on any of the tires on your cars either. The wheels are countersunk and the nuts are chamfered, (spelling???) which increases the contact point and is so designed that they don't backoff and get loose. I can also tell you that I never seen a car loose a wheel other then for a bearing or something like that. Guess others have though. The nuts and lugs are the same for cars, same for trailers. So how is it that cars don't have to be checked?
> 
> I'm all ears, educate me but I don't buy the scraping arguement at all, our rear wheels scrape in our cars and trucks albeit with less of a moment arm. With tight lugs the pressure is now on the bearings.


Mike, I'm guessing it is the lug material. If you need to re-torque (and I definetly beleive that you do), there's only a few reasons:
1. Nut is backing off
2. Material being clamped is collapsing
3. Lug is stretching

For #1, this would be possible if you didn't have enough torque.... I'm goint to assume that the 120 ft-lbs is sufficient since it is pretty high, but I won't guarentee it.

#2 is a possibility, but I would think less so on steel wheels. Incidentally there was a owner notification for some Automotive aluminum wheels about a decade ago. It asked that they be re-torqued after a particular time in service.

That leaves #3. Bolts (and I'm assuming lugs) can be made in various different property grades depending on what loads you are looking for. Perhaps the axle manufacturers have speced out a material that just relaxes over time.









Incidentally, it is a Very good idea to torque the lugs on your car with a torque wrench. I do it every time I rotate the tires and I watch the mechanics do it when I get new tires. Insufficient or excessive torque can cause the joint to fail, and I'd rather keep all my wheels attached.


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## PDX_Doug (Nov 16, 2004)

I do 94 pounds on my alloy wheels. Used to do 120 on the steel wheels.

As has been suggested in the past, we don't check are car/truck wheels every time we go driving, but as has also been said it doesn't take long either. And offers a lot of piece of mind.

Happy Trails,
Doug


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## CamperAndy (Aug 26, 2004)

NJMikeC said:


> I have yet to get a good explanation about this. I easily put on an took off 1000's of tires in my life, never lost a one and never used a torque wrench. I can also nearly guarantee you that you never got a torque wrench put on any of the tires on your cars either. *The wheels are countersunk and the nuts are chamfered, (spelling???) which increases the contact point and is so designed that they don't backoff and get loose*. I can also tell you that I never seen a car loose a wheel other then for a bearing or something like that. Guess others have though. The nuts and lugs are the same for cars, same for trailers. *So how is it that cars don't have to be checked*?
> 
> I'm all ears, educate me but I don't buy the scraping arguement at all, our rear wheels scrape in our cars and trucks albeit with less of a moment arm. With tight lugs the pressure is now on the bearings.


The chamfer preforms a wheel centering function, not to prevent the nut from coming loose.

Consistent torque is more important then an absolute value. thus your years of tire changes without a lost wheel. Think about haw you do it and you will realize that without trying too hard you naturally try to put the exact same pressure on each nut. As for my wheels, they have always seen a torque wrench for the last 25 years or so.

Cars should be checked also but it is more critical for aluminum wheels due to metal yield. When we put new wheels on my sons car a couple of years ago, there was a steering wheel cover that said to please return to the tire store once the car had been driven 100 miles so that the tires could be rechecked.


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## Carey (Mar 6, 2012)

One reason trailers wheels need retorqued is they can loosen over time from the side loading that occurs.. Yes Ive never lost one either. Ive personally seen prolly 10 come off while driving all the millions of miles ive done.. Its a huge problem out here.

I also believe that when making a very tight corner and sliding the trailer wheels, that a stud can stretch a bit.. Not much, but a bit.

Semi wheels now use a single stud and lug nut rather than a double lug nut.. Much safer..

Race cars have a problem with loosening wheel nuts too from the extreme side loading that is happening... Same for your RV..

We torque them all at 120 steel or alum. Thats what they ask us to do, so I do what the mfr's tell us.. 120 will not hurt a wheel and if something happens Ive done whats been asked of me..

Carey


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## NJMikeC (Mar 29, 2006)

Colorado~DirtBikers said:


> 120 will not hurt a wheel and if something happens Ive done whats been asked of me..
> 
> Carey


Best , argument I have heard yet!

We got extreme lateral forces since we scream our trailers around corners .99% of the time. Then the streching bolt theory that could be combatted by better bolts since it is so mission critical. Face it, the bearings have a tougher time of it via cornering but we don't beat ourselves silly over those.

So maybe these are right but I can't say I'm too convinced.

Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


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## CamperAndy (Aug 26, 2004)

NJMikeC said:


> Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


The studs are placed in precise location, relative to the center of the hub so they are effectively working as centering devices. The holes are over sized in the wheels to the studs so you are less likely to damage the threads of the stud when placing the wheel of the axle. The nuts are chamfer to center the wheel to the studs and thus centering the wheel to the hub. If it were only or even mostly about locking the nut on the stud there would be a locking device other then just surface area of the chamfer and if surface area were the objective then an over sized nut relative to the stud would be used and be less costly to manufacture.


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## Carey (Mar 6, 2012)

Heres another oddity Mike.. I have never, never seen a trailer wheel that uses 8 lug nuts come off.. Ive seen countless 5 lug wheels fall off.. Yes utility trailers lose more wheels than rv's do.. More of the utility trailers lose wheels from wheel. stud, and bearing failures than rv's do..

I have no idea why this is.. I know I torque alot of wheels and when I retorque them the 5 lug wheels are looser than the 8 lug wheels.. 8 lug wheels seem to hold there torque better.

Semis and my dually too use a lug nut with a washer attatched to it.. The wheel, mine included dont use a chamferred hole.. The washer is meant to help the nut keep its torque and spread the load..

I dont know the name of these lug nuts, but im sure theres info if you look..

I know we dont do sit and spins with the tires on cars.. We sure do on trailers though.. Not supposed to but we all do from time to time.. I would gamble this is very hard on the studs, especially 5 bolt studs..

A 5 bolt wheel has more space between the lug nuts than 8 lug wheels do to.. Maybe has something to do with it too..

I have no clue, Im just guessing.

Carey


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## CamperAndy (Aug 26, 2004)

Carey,

Here is your Semi wheels. They do not use chamfers nuts but rely on a machined fit between the ID of the wheel and the OD of the hub. The torque is so high on these wheels that a chamfered nut would distort the wheel, so they use the flanged nuts to retain the wheels. The cost to match machine the wheels to match the hubs would add significantly to the cost of trailer wheels which are stamped.


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## Nathan (Jan 2, 2007)

I'm betting the deal on utility trailers is maintenance. I'm guilty of it as well. I keep good maintenance on the expensive RV, but on the cheap utility trailer, I can't tell you when was the last time the bearings were greased.


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## Carey (Mar 6, 2012)

Thanks Andy, that explains why I have seen guys have to use sledges to break lose the wheel from the hub.. I have to do that to with my dually, so I use some antisieze which helps if I dont leave em on to long..

Carey


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## NJMikeC (Mar 29, 2006)

CamperAndy said:


> Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


The studs are placed in precise location, relative to the center of the hub so they are effectively working as centering devices. The holes are over sized in the wheels to the studs so you are less likely to damage the threads of the stud when placing the wheel of the axle. The nuts are chamfer to center the wheel to the studs and thus centering the wheel to the hub. If it were only or even mostly about locking the nut on the stud there would be a locking device other then just surface area of the chamfer and if surface area were the objective then an over sized nut relative to the stud would be used and be less costly to manufacture.

[/quote]

Interesting-- I could give a child an axle and a wooden wheel and ask them where they drill the hole to center the wheel on the axle and they could figure it out via trial and error. Yet you would have us believe that drilling holes around the periphery and then counter sinking them would be better, simpler. all the while ignoring the obvious.

Certainly something missing in this especially concerning how chamfering is used in automated assembly proceess which of course is outside of this application but I'm done with this anyways, believe what you will.

Torque away, nothing wrong with it, guess it makes people safe and suppose that works.


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## CamperAndy (Aug 26, 2004)

NJMikeC said:


> Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


The studs are placed in precise location, relative to the center of the hub so they are effectively working as centering devices. The holes are over sized in the wheels to the studs so you are less likely to damage the threads of the stud when placing the wheel of the axle. The nuts are chamfer to center the wheel to the studs and thus centering the wheel to the hub. If it were only or even mostly about locking the nut on the stud there would be a locking device other then just surface area of the chamfer and if surface area were the objective then an over sized nut relative to the stud would be used and be less costly to manufacture.

[/quote]

Interesting-- I could give a child an axle and a wooden wheel and ask them where they drill the hole to center the wheel on the axle and they could figure it out via trial and error. Yet you would have us believe that drilling holes around the periphery and then counter sinking them would be better, simpler. all the while ignoring the obvious.

Certainly something missing in this especially concerning how chamfering is used in automated assembly proceess which of course is outside of this application but I'm done with this anyways, believe what you will.

Torque away, nothing wrong with it, guess it makes people safe and suppose that works.
[/quote]

Mike you can not convince everyone even if it is obvious what the answer is so try this. Put some fender washers on the studs and turn the nuts over so the flats are holding the washers in place and then see if your trailer wheels are centered on the hubs.

BTW the steel wheels are stamped/punched not drilled.


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## Nathan (Jan 2, 2007)

CamperAndy said:


> Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


The studs are placed in precise location, relative to the center of the hub so they are effectively working as centering devices. The holes are over sized in the wheels to the studs so you are less likely to damage the threads of the stud when placing the wheel of the axle. The nuts are chamfer to center the wheel to the studs and thus centering the wheel to the hub. If it were only or even mostly about locking the nut on the stud there would be a locking device other then just surface area of the chamfer and if surface area were the objective then an over sized nut relative to the stud would be used and be less costly to manufacture.

[/quote]

Interesting-- I could give a child an axle and a wooden wheel and ask them where they drill the hole to center the wheel on the axle and they could figure it out via trial and error. Yet you would have us believe that drilling holes around the periphery and then counter sinking them would be better, simpler. all the while ignoring the obvious.

Certainly something missing in this especially concerning how chamfering is used in automated assembly proceess which of course is outside of this application but I'm done with this anyways, believe what you will.

Torque away, nothing wrong with it, guess it makes people safe and suppose that works.
[/quote]

Mike you can not convince everyone even if it is obvious what the answer is so try this. Put some fender washers on the studs and turn the nuts over so the flats are holding the washers in place and then see if your trailer wheels are centered on the hubs.

BTW the steel wheels are stamped/punched not drilled.
[/quote]
Please don't do that before towing anywhere near where I am...









The 3/8" nut requiring 3/8" of thread is a typical rule of thumb. However there are grades of bolts, etc which change this rule.


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## Carey (Mar 6, 2012)

Nathan said:


> Chamfering may serve to center but if you want to center something don't you do it around the center as in the hub? Simple fastener science, I think it goes like this, a 3/8" nut only requires 3/8" of thread contact and that is all the holding power you ever get, then you get washers or a countersink to increase contact area.


The studs are placed in precise location, relative to the center of the hub so they are effectively working as centering devices. The holes are over sized in the wheels to the studs so you are less likely to damage the threads of the stud when placing the wheel of the axle. The nuts are chamfer to center the wheel to the studs and thus centering the wheel to the hub. If it were only or even mostly about locking the nut on the stud there would be a locking device other then just surface area of the chamfer and if surface area were the objective then an over sized nut relative to the stud would be used and be less costly to manufacture.

[/quote]

Interesting-- I could give a child an axle and a wooden wheel and ask them where they drill the hole to center the wheel on the axle and they could figure it out via trial and error. Yet you would have us believe that drilling holes around the periphery and then counter sinking them would be better, simpler. all the while ignoring the obvious.

Certainly something missing in this especially concerning how chamfering is used in automated assembly proceess which of course is outside of this application but I'm done with this anyways, believe what you will.

Torque away, nothing wrong with it, guess it makes people safe and suppose that works.
[/quote]

Mike you can not convince everyone even if it is obvious what the answer is so try this. Put some fender washers on the studs and turn the nuts over so the flats are holding the washers in place and then see if your trailer wheels are centered on the hubs.

BTW the steel wheels are stamped/punched not drilled.
[/quote]
Please don't do that before towing anywhere near where I am...









The 3/8" nut requiring 3/8" of thread is a typical rule of thumb. However there are grades of bolts, etc which change this rule.
[/quote]

Very true Nathan..

Dont worry Mike you are in the vast majority of people who dont torque wheels by far... So in the end if you feel better your way is superior and few actually go by the book...









Im one who, if I can find a way to get the room to fit a torque wrench I use it on every thing.. I have torque all my wheels, car or whatever for 25 years.. Yea dude I even torque my valve cover bolts..

Heres my reason. Im 6-4 280lbs and built like a tank.. My arms are the size of most guys legs.. lol I can twist off wheel studs like most guys twist off valve cover bolts... I learned at a young age, that going by the feel doesnt work for me.. My feel is twice the amount of tightness.. 
Who really cares dude.. I have learned pretty well to dodge wheels flying off stuff out there.. Its no biggie..

Dont get your fellings hurt on us..

Carey


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