Hub axle pins. What are these? (1 Viewer)

[jvincig01]

I am missing 3 of the 4 pins that are on my hubs. On one of the hubs, they are completely sheered off inside, and they are not coming out.

Do I actually need these?

 

[JAG666]

HELL YES, You NEED these!!! They keep the LC's Rims from cutting the lug studs off!!
Think of the song: You Took A Fine Time To Leave Me, Loose Wheel!!
Charles '74 FJ4- (Bought new Dec. 1973)

 

[Malleus]

EDIT: I have to apologize for a brain fart earlier; my previous posts referenced 80 series hubs; I had 80s on the brain while I was reading.

The 40 series hubs are NLA (why can we get hood hardware and fender badges, but not hubs), however, you can get used:
BTB (the old Man-A-Fre) has them:

Classic Cruisers in Poncha Springs, CO may have them too.

That's a really good question. Those "pins" are hardened dowel pins; they're pressed in and if they're broken, there's no way I know of, short of cutting the hub, to remove them. Of course, that would defeat the point of fixing the hub...

Dowel pins are typically used to locate two components, relative to each other, so that they can be attached, usually by means of screws of bolts and nuts, or in this case, studs and nuts.

The hub subassembly should have been provided with two dowels, presumably to use as drivers for the drive flange - the idea is that the drive flange needs a reaction arm, in this case two, so that when the driveshaft splines turn, and thus turn the flange, the hub turns with it. You'd think that with six studs to engage the drive flange, it would be pretty well attached to the hub. Toyota engineers probably felt that the purpose of the studs, cone washers and nuts were to provide the clamping force necessary to securely attach the drive flange to the hub, and that for off-road use, additional torsional reaction would be needed.

This is because the holes that the studs fit into are clearance holes, and the drive flange would have to turn a bit to engage the sidewall of the hole with the stud, in order to "drive" the drive hub via the flange. The dowels, on the other hand, are press fit into the hub, just to keep them from falling all over the place during hub service, and slip fit into the drive flange. If you place a drive flange over the hub and engage the pins, you'll notice there is no rotational play between the two. This keeps them in constant contact and lessens the shock load when the driveshafts change rotation, or the load is released and reapplied, such as when you work the throttle back and forth.

FWIW, the clearance holes are part of the reason for the cone washers.

Short answer, if they broke on the trail, I'd drive it out, but I'd be careful with it. If they broke on the road, I'd place finding out why high on my list, and replace the hubs as soon as I could. If you're driving only on the road, you'll probably be OK for a good while. It's entirely possible, if one or more are gone, they just fell out. You can buy standard metric dowels and replace them, if they aren't broken (sheared off) in the holes. There's nothing magic about them.

You can buy new hubs (unfortunately they come with bearings, but not studs), or just replace yours with used ones. @slow95z or @arcteryx can probably help you out.

Toyota sells the dowels, but for my money, that's like buying Toyota gasoline. Dowels are dowels.

They look to be Ø7-mm and maybe as long into the hub as out - 20-mmm maybe?

 

[slow95z]

I have used hubs but I see no reason not to just buy new dowels and go that way

 

[pjohnson]

Broken pins can be removed much the same way as a broken bolt or stud. They are more difficult to drill out since they are hardened. However, the hardened area is typically the outer portion of the pin, the center being softer and therefore, drillable.
They break because the hub nuts are not kept tightened and the hub top cover shears them off along with the studs. Your studs were replaced at some point without replacing the pins.
If it's not in your capabilities to remove them, a competent machine can do it. Toyota OEM pins will be the exact correct size, so for my money, I would go OEM.

 

[jvincig01]

EDIT: I have to apologize for a brain fart earlier; my previous posts referenced 80 series hubs; I had 80s on the brain while I was reading.

The 40 series hubs are NLA (why can we get hood hardware and fender badges, but not hubs), however, you can get used:
BTB (the old Man-A-Fre) has them:
View attachment 3369225

Classic Cruisers in Poncha Springs, CO may have them too.

That's a really good question. Those "pins" are hardened dowel pins; they're pressed in and if they're broken, there's no way I know of, short of cutting the hub, to remove them. Of course, that would defeat the point of fixing the hub...

Dowel pins are typically used to locate two components, relative to each other, so that they can be attached, usually by means of screws of bolts and nuts, or in this case, studs and nuts.

The hub subassembly should have been provided with two dowels, presumably to use as drivers for the drive flange - the idea is that the drive flange needs a reaction arm, in this case two, so that when the driveshaft splines turn, and thus turn the flange, the hub turns with it. You'd think that with six studs to engage the drive flange, it would be pretty well attached to the hub. Toyota engineers probably felt that the purpose of the studs, cone washers and nuts were to provide the clamping force necessary to securely attach the drive flange to the hub, and that for off-road use, additional torsional reaction would be needed.

This is because the holes that the studs fit into are clearance holes, and the drive flange would have to turn a bit to engage the sidewall of the hole with the stud, in order to "drive" the drive hub via the flange. The dowels, on the other hand, are press fit into the hub, just to keep them from falling all over the place during hub service, and slip fit into the drive flange. If you place a drive flange over the hub and engage the pins, you'll notice there is no rotational play between the two. This keeps them in constant contact and lessens the shock load when the driveshafts change rotation, or the load is released and reapplied, such as when you work the throttle back and forth.

FWIW, the clearance holes are part of the reason for the cone washers.

Short answer, if they broke on the trail, I'd drive it out, but I'd be careful with it. If they broke on the road, I'd place finding out why high on my list, and replace the hubs as soon as I could. If you're driving only on the road, you'll probably be OK for a good while. It's entirely possible, if one or more are gone, they just fell out. You can buy standard metric dowels and replace them, if they aren't broken (sheared off) in the holes. There's nothing magic about them.

You can buy new hubs (unfortunately they come with bearings, but not studs), or just replace yours with used ones. @slow95z or @arcteryx can probably help you out.

Toyota sells the dowels, but for my money, that's like buying Toyota gasoline. Dowels are dowels.

They look to be Ø7-mm and maybe as long into the hub as out - 20-mmm maybe?

This is VERY helpful. Thank you! I will be looking around for a replacement.

 

[3_puppies]

HELL YES, You NEED these!!! They keep the LC's Rims from cutting the lug studs off!!
Think of the song: You Took A Fine Time To Leave Me, Loose Wheel!!

the missing pins are for the locking hubs or drive plates, NOT the rim to hub

 

[dirtyham]

Cut and file them back flush with the flange face and drill 2 new holes opposite sides

 

[dirtyham]

Broken pins can be removed much the same way as a broken bolt or stud. They are more difficult to drill out since they are hardened. However, the hardened area is typically the outer portion of the pin, the center being softer and therefore, drillable.
They break because the hub nuts are not kept tightened and the hub top cover shears them off along with the studs. Your studs were replaced at some point without replacing the pins.
If it's not in your capabilities to remove them, a competent machine can do it. Toyota OEM pins will be the exact correct size, so for my money, I would go OEM.

check the diff housing isnt bent as well another common cause of broken studs and dowels

 

[too tall]

Or you could drill out the holes in the lockout body to accept 7/16" fine thread bolts and re-tap the hubs to accept the larger fasteners. No more dowel pins needed. Most domestic full float hubs have no dowel pins, the fasteners are big enough to withstand the torque. Keep em' tight and you'll be alright.

 

[royal cake]

I had the same issue with one of the pins. I tried drilling it out, but then the pin started spinning. I was able to get a smaller hardeded bit and drilled a small hole in it, then was able to pull it out.
I can't remember at the moment if I bought a new pin or turned one on the lathe.

Builds - 1969 FJ40 Father / Son Build

Shane If you look carefully at your pic, you’ll notice that the bushing that is higher in the pic has a ‘flat’ in its taper at the end closest to the taper of the spindle. The lower bushing does not have a flat. That is a sign that either the lower bushing is worn, OR (and I have seen this...

forum.ih8mud.com

 

[pbgbottle]

I probably wouldn’t worry about them , those studs get squeezed pretty good by the cone washers I don’t think anything should move if ya keep them nuts tight. ..
I don’t even know how you would damage one of those. Crazy.

 

[jvincig01]

Cut and file them back flush with the flange face and drill 2 new holes opposite sides

I ended up doing this, and it worked like a charm. Fortunately, I have a 7mm drill bit. Took my time measuring the hole placement because its a tight fit.

 

[Shark56]

My stud pins were ok but I put this kit in.

ARP Hub Stud Kits (black)

We now have a hub upgrade for solid axle front ends, our Full-Floating rear end, and Land Cruiser front ends! […]

www.yotamasters.com

 

[jim land]

New aftermarket hub do exist @Malleus

Solid Axle Hub

Solid Axle Hub

trail-gear.com