What's poorly engineered about the wheel hub?

What happened to yours?

 

What's poorly engineered about the wheel hub is that you you can't replace a wheel stud because the knuckle is in the way. You have to pay a lot of money to a professional shop to remove the hub and reinstall it, which disturbs the wheel bearing, just in order to replace a $2 stud - something that often gets cross-threaded, corroded, stretched, bent, or snapped.

 

I seem to remember someone on youtube grinding off part of the head which allowed the stud to be hammered in from behind hub assy.

Maybe not! See following thread.
http://www.mdxers.org/forums/18-maintenance/40932-replacing-wheel-stud.html

Lots of videos on youtube. This may provide some ideas for MDX.

Found this thread that may help.

http://www.mdxers.org/forums/18-maintenance/105826-replace-broken-wheel-stud-front.html

good luck

 

Thanks Tex - I was stuck in a tire shop, and they tried the grinding trick and it really didn't seem like the Dorman studs were going to go in with any amount of hammering. So we went the long yucky route and put in a new wheel bearing while it was apart, and 4 new studs (that's all I had on hand). After 4.5 hours, it was all fixed, but seriously - I don't ever want to have to do that again.

So the original question stands - has anyone ever done this, and is there an obvious drawback?

 

I don't mean to downplay your situation, because no matter what it really sucks when a project is bigger than it should be, and when you are paying for it to be done, it always hurts the wallet.

But, I don't think wheel studs are really a constantly serviced item. Personally I have, nor have I when I took any of my vehicles anywhere for tire service, ever had a wheel stud problem.

Much of the problems you suggest are the result of improper workmanship, most of which probably involved an impact, in the hands of someone who didn't really know what they were doing.

Here is something else to think about. Engine Camshaft timing belts, are considered serviceable parts, yet you have to tear the engine compartment at least somewhat apart to change them depending on the model you have. Nobody really accepts this concept as poor engineering.

Bottom line it sounded like you needed a new wheel bearing anyway, exactly why is this such a horrible design again?

 

But, I don't think wheel studs are really a constantly serviced item. Personally I have, nor have I when I took any of my vehicles anywhere for tire service, ever had a wheel stud problem.

I'm not going to debate that point, though it would be interesting to see data on stud sales and replacement. Hope your luck keeps up.

Much of the problems you suggest are the result of improper workmanship, most of which probably involved an impact, in the hands of someone who didn't really know what they were doing.

Right, well, any time a tire is taken off and put back on, there's the torque required to remove the lug nut, which for several reasons is greater than the 80 ft-lb to put it on. Then, as you point out, they are probably all put back on with an impact wrench and a "spud". Most people have no control over that and can't always be present or pissing off the guy who's "been doing it [wrong] for XYZ years."

Here is something else to think about. Engine Camshaft timing belts, are considered serviceable parts, yet you have to tear the engine compartment at least somewhat apart to change them depending on the model you have. Nobody really accepts this concept as poor engineering.

I think those things are apples and oranges. The timing belt is INSIDE the engine in a manner of speaking, and so naturally it MUST be disassembled to change it out, and I believe that ALL engines are built this way.
In the present case, there are myriad cars that don't have to have the hub removed to replace a simple stud, it's on the outside of the vehicle, and given that there's an alternative method of attaching the stud from the FRONT face of the hub, and that method was not chosen even in the face of the fact that attaching them from the rear REQUIRES that the hub be removed, then I'd say that it was poor engineering.

Bottom line it sounded like you needed a new wheel bearing anyway, exactly why is this such a horrible design again?

I did NOT need a new wheel bearing. I needed a new stud, and the second one was visibly stretched. Replacing even one stud required pulling the hub at least partway off, which would disturb the bearing, and "since we're already in there" / it's an '02 / and a bearing was "only $40 more", I made the executive decision to replace the bearing so I didn't have to have it take a SH** in the middle of the highway, at night, on a holiday weekend, in BFE, with no money and no cell signal. "Cheap insurance", sure, but an unnecessarily expensive and complicated stud replacement requiring a lift, disassembly of axle components, specialized tools, and unnecessarily opening up a can of worms and disturbing a sensitive and critical component to achieve what in billions of other cars is a simple repair.
Plus the added _hours_ of shop time inconveniencing me, taking up lift time in the shop, and denying other customers the opportunity to have _their_ cars serviced because of the delay.

I'd respectfully request that this not serve as the "unzipping of the fly" in a pissing match - I was just asking a simple question, and I wanted to focus on my original question and perhaps learn something useful.

"Can a wheel be converted from studs pressed in from the rear to studs screwed in from the front without detriment to function and safety?"
That's all.

Hope you have a great day. Safe traveling.

 

I think I have only seen wheel studs in this manner. While you might have to replace the stud, I don't think it's a design issue more-so you're just mad that "it could have been simpler".

I haven't had to replace a wheel stud either and have helped others replaced theirs. It was by choice (longer wheel studs) to accommodate different rims.

Back to your original question, I bet it boils down to it works and probably is the safest / most effective / probably cheapest. There is no way that stud could back out for any reason other than to break off (which probably means bigger issues).

 

FWIW, I agree that Acura could have easily modified the knuckle hub to allow stud replacement w/o disassemblying the wheel bearing. It would only take an 6-8 mm groove in side of knuckle to allow w/o modifying the stud. You would still need to cut out part of dust shield to facilitate.

I don't see any problems w/ grinding part of the stud away. there remains plenty of stud head available to transfer bolt loads to the wheel flange. In the pics accompanying the post by ChrisMDXER, I would estimate that 40% of stud head is removed, and perhaps 20% of stud body. I would not hesitate to do this mod to avoid removing wheel bearing.

good luck

 

You would still need to cut out part of dust shield to facilitate.

We did at the start, then completely removed it.

I don't see any problems w/ grinding part of the stud away. there remains plenty of stud head available to transfer bolt loads to the wheel flange.

When I discussed this with the parts department at the Honda dealer, the mechanic said the only concern might be non-uniform distribution of the clamping load which might allow movement of the stud in the hole and consequent rounding out of the hole in the hub - movement like the precession of a rotating ... lead object.

In the pics accompanying the post by ChrisMDXER, I would estimate that 40% of stud head is removed, and perhaps 20% of stud body. I would not hesitate to do this mod to avoid removing wheel bearing.

I didn't hesitate for a second.
The mechanic ground off nearly 50% of the head, and a bit of the serrated body. It STILL didn't seem like there was any way it was going in.

I used Dorman studs I got at Autozone.
Thread Size: M12-1.50
Knurl Diameter (In): 0.487 Inch
Knurl Diameter (mm): 12.37mm
Length (mm): 42mm
Shoulder Length (In): 0.433 Inch
Shoulder Length (mm): 11mm

Maybe there are studs of another (shorter?) dimension that allow easier replacement?

With regard to the backing-out issue that ptrd raised, I would imagine that something simple like tapered thread, thread lock, jamb nut, or castle-nut and cotter-pin would prevent spontaneous loosening, just to throw a few common options out off the top of my head. Though if you look at the photos of the studs in the links, there is no provision, and presumably no necessity for such an additional means of securing the studs in the hubs.

My primary goal is still not to ***** - though I'm not averse to incidental venting - it's to learn something about the engineering specs of the wheel studs. Is there a drawback to using screw-in studs? I would imagine that if the torque for the stud is higher than the lug nut, the retaining force would prevent the stud from being over-torqued past the yield point (assuming the lug nuts are correctly torqued). Speculation doesn't do much good.