Directional Tyres

[carmanmemoranda]

20 years in the motor trade and I’ve never heard anyone say anything remotely like that. The wheel nut is the most important part and grease on the hub, nut flange etc will have no negative effect as the nut/s hold the wheel on.

Every loose wheel I’ve ever seen has had slack or missing wheel nuts.

Qualified ?

 

[Ivor Windybottom]

Every loose wheel I’ve ever seen has had slack or missing wheel nuts.

Absolutely. If you loosen the bolts then you reduce the friction between the wheel and hub.

It's a weird concept, but the bolts do not hold the weight of the car, and are probably not strong enough to do this, they just squeeze two surfaces hard enough together that they can't move. If you could insert a zero friction layer between the hub and wheel then the bolts would snap, even if tightened.

So greasing the surface is probably not a good idea.

 

[Deleted member 221031]

Absolutely. If you loosen the bolts then you reduce the friction between the wheel and hub.

It's a weird concept, but the bolts do not hold the weight of the car, and are probably not strong enough to do this, they just squeeze two surfaces hard enough together that they can't move. If you could insert a zero friction layer between the hub and wheel then the bolts would snap, even if tightened.

So greasing the surface is probably not a good idea.

I’m not going to be baited. If you don’t think the wheel is held on by the nuts when properly torqued up I can’t help you.

Next you’ll be saying don’t grease the threads lol.

 

[Deleted member 221031]

On a Range Rover service sheet it is a service item to remove the wheel and apply some anti-seize lubricant between the two.

As with many cars.

 

[carmanmemoranda]

As with many cars.

Rubbish

 

[Ivor Windybottom]

I’m not going to be baited. If you don’t think the wheel is held on by the nuts when properly torqued up I can’t help you.

Next you’ll be saying don’t grease the threads lol.

Sorry you can't understand. I've attempted to explain in Sesame Street language, I'll give up as I'm getting nowhere.

 

[Deleted member 221031]

Sorry you can't understand. I've attempted to explain in Sesame Street language, I'll give up as I'm getting nowhere.

Wheels are held on by wheel nuts. And need to be correctly torqued and sometimes re torqued later on.

What can’t you grasp ? It’s not friction it’s the force of the wheel nut.

No need to be rude, you’ve pulled others for similar.

 

[Deleted member 221031]

Wheels are mainly torqued in NM https://en.wikipedia.org/wiki/Newton-metre

 

[Ivor Windybottom]

Wheels are held on by wheel nuts. And need to be correctly torqued and sometimes re torqued later on.

What can’t you grasp ? It’s not friction it’s the force of the wheel nut.

No need to be rude, you’ve pulled others for similar.

Sorry, was getting annoyed as you appeared to be deliberately missing what I thought was a fairly simple point.

If we're getting really fundamental then bolts are only held in by friction anyway. If there was no friction in the threads they'd spin out as soon as a load was applied.

It's just physics.

 

[Ivor Windybottom]

Wheels are mainly torqued in NM https://en.wikipedia.org/wiki/Newton-metre

Bolts are at risk of being over-tightened if you grease them, as the friction in the threads is what pushes back to create the torque that you measure.

At a given torque setting, a greased bolt will end up squeezing much tighter than an ungreased one. If you tighten with grease then it may be at higher risk of becoming stuck when that grease degrades over time, as it will be tighter.

Reduced Torque with Lubricated Bolts

Lubrication effect on bolt tension and torque.

www.engineeringtoolbox.com

Note that if torque specified for a dry or slightly oiled bolt torque is applied to a lubricated bolt - the bolt may overload and break.

 

[Deleted member 221031]

Sorry, was getting annoyed as you appeared to be deliberately missing what I thought was a fairly simple point.

If we're getting really fundamental then bolts are only held in by friction anyway. If there was no friction in the threads they'd spin out as soon as a load was applied.

It's just physics.

I appreciate the apology.

A wheel is held on primarily by the force of the wheel nut. Take the nuts off and friction won’t keep it there.

I don’t want to fall out, you’re one of the good guys in here

 

[Deleted member 221031]

Bolts are at risk of being over-tightened if you grease them, as the friction in the threads is what pushes back to create the torque that you measure.

At a given torque setting, a greased bolt will end up squeezing much tighter than an ungreased one. If you tighten with grease then it may be at higher risk of becoming stuck when that grease degrades over time, as it will be tighter.

Reduced Torque with Lubricated Bolts

Lubrication effect on bolt tension and torque.

www.engineeringtoolbox.com

Note that if torque specified for a dry or slightly oiled bolt torque is applied to a lubricated bolt - the bolt may overload and break.

I think you might be over thinking it, I was stating a wheel nut holds a wheel on. Which is true

Feel free to take yours off and drive home ?

 

[carmanmemoranda]

Bolts are at risk of being over-tightened if you grease them, as the friction in the threads is what pushes back to create the torque that you measure.

At a given torque setting, a greased bolt will end up squeezing much tighter than an ungreased one. If you tighten with grease then it may be at higher risk of becoming stuck when that grease degrades over time, as it will be tighter.

Reduced Torque with Lubricated Bolts

Lubrication effect on bolt tension and torque.

www.engineeringtoolbox.com

Note that if torque specified for a dry or slightly oiled bolt torque is applied to a lubricated bolt - the bolt may overload and break.

Good, correct information

 

[ericmark]

I started to read, I remember the argument, do you want grip in or out of the salt, this was clearly with a digger, but paddles were directional back in the 50's on tractors etc.

So do you want grip accelaring or stopping? The same tyre went one way around on diggers, the other on tractors.

 

[fixitflav]

I would say that everyone who is capable of changing a wheel at the roadside should take them off one at a time before you need to and clean the mating faces between the flange/hub and the wheel rim with a wire brush, paying extra attention to the locating spigot that goes into the wheel rim and apply some grease between them. I have had a few cars in that even with garage equipment to hand have been very difficult to separate. I’m talking about some heavy hitting on the inside of the rim with a hide hammer while rotating the wheel. I would have had no chance of getting the wheel off on the road.

This gives you an idea although I’ve had some that just will not kick off. If you don’t have a heavy hide hammer, perhaps use a block of wood on the inner rim and a hammer. It’s rare, but not something extra you want to be dealing with when you have a puncture.

I had that problem many years ago, first time I tried to get a wheel off a Mondeo (on alloys). it was such a good fit on the raised part of the hub it wouldn't come off. I had to get behind it with a chisel and give it a right pounding. But it wasn’t due to adhesion between the wheel and the face of the hub. Lucky not a flat tyre in the middle of the night in the rain.

I had a go at the hole in the wheel with wire brush and emery paper, but it wasn't enough, the wheel studs were pulling it on to the hub. So I attacked it (and the others, naturally) with a half-round file, and was OK after. And gave it a smear of grease, naturally.