Wheel nuts - fit dry, or with neversieze?

[Aussie Jeepster]

I'm going to be changing my wheel nuts over this weekend to Tuffant solid ones.
I'll torque them to 140nm which I believe is the right figure.
But I have a question.
I've seen others say they squirt the studs with WD40/CRC, and other use Copper Eze or Permatex Anti-Seize - is this a good idea? I know in the UK salt on the roads causes major grief, but as we dont have that issue here, is it ok to just fit them dry, and check them every 50km or so to make sure they stay torqued up?
Thanks
Alan

[scarry]

Here we go again.....

I grease them,light smear,but others say dry.

[p38arover]

I usually use engine oil on wheel studs. Whether one should reduce the torque setting - I don’t know. I doubt the factory uses dry threads on the studs and nuts.

I put anti-seize on the centre hub to stop the alloy rims corroding onto the hub.

[AK83]

I use anti seize.

I think part of the problem is that they self tighten as you drive ... not just the possibility of rust salty environment, but that they are down low on the vehicle and that's usually the most prone to moisture. I know this sounds obvious, but any moisture on steel and it rusts over time.
Also, do you go to beach areas? Do you drive through deep water etc?

If you don't regularly check them, like myself, then over time, a bit of rust and the self tightening issue just makes it harder for no reason. anti seize just helps at some point down the road.

The worst vehicle I've had to deal with with wheel nuts/studs was the old International C1300 truck my father had for his delivery business. Diabolical when it came to studs, they would always snap not having touched them at all, and for sure would snap in many instances when removing wheel. One time I recall needing to change a front tyre and of the 8 studs 3 snapped trying to remove the nuts.

I dunno about spraying with WD type stuff tho, got to be careful not to get any overspray on the disc of course. A dab of anti seize is no issue, and in the years I've done it never seen any of the issues that some propose.

[Tins]

Like Paul says, here we go.....

D2s have the same issue. I don't oil the threads, and have never seen the practice*, but I def use anti seize between the wheel boss and the hub, and the outside of the nuts.

* Not saying it's wrong, Ron.

[B.S.F.]

Just ask yourself why there are so many Series vehicles with broken missing or loose wheel studs, and then decide for yourself.
.W.

[JDNSW]

My experience with over sixty years of driving four wheel drives is that unlubricated studs will seize sooner or later. I don't think it makes much difference what lubricant you use. i usually use anti-seize, but will use any available oil if necessary.

How essential it is will depend mainly on how humid the environment is.

[101RRS]

Just ask yourself why there are so many Series vehicles with broken missing or loose wheel studs, and then decide for yourself.
.W.

Well don't keep us in suspense - why?

[DiscoDB]

You actually need to know the grade of the stud to know if adding a lubricant will lead to over-torquing at 140Nm. The typical accepted clamp force is based on achieving 75-90% proof load and this is dependent on the grade of the bolt (stud in this case) and the thread coefficient of friction (dry or lubricated).

Unfortunately the studs have no grade stamped on them, and the only individual studs you can buy are aftermarket.

The aftermarket studs are typically grade 10.9, and so torqued up to 140Nm dry or lubricated will always be well below the yield point (between ~50% and ~70% proof load).

BUT - if the original studs are only grade 8.8 (and this is very possible as this is a more durable grade to use), then 140Nm for a dry connection will take the M14 stud to somewhere around the recommended 75% proof load point. Add a lubricant, the K factor drops, and 140Nm can take it to the yield point - that is you risk stretching the stud. May not fail, but repeatedly done, or over-torqued because you don’t use a torque wrench, and it will eventually snap.

The LR workshop manual says all bolts and nuts are to be fitted dry “unless stated otherwise”. In this case we have to assume this also applies to wheel nuts as they don’t state otherwise.

However, if you do add lubricant you should just lower the torque setting to compensate and keep the bolt tension in the optimum 75-90% proof load range (unless you know for a fact they are grade 10.9 studs).

And if anyone does know for a fact what the original grade the studs are (not aftermarket ones), please post the details.

[DieselLSE]

[QUOTE=DiscoDB;3195629]Add a lubricant, the K factor drops, and 140Nm can take it to the yield point [QUOTE]

Can you explain this for numpties? I don't understand how a little bit of lubricant can dramatically affect the yield point.

[DiscoDB]

Up to 80-90% of the torque being applied is just to overcome the frictional losses - this is both friction on the thread, and friction of the mating surfaces at the head. Only 10-20% goes into tensioning the bolt.

When you add some lubricant, you reduce the amount of friction on the thread and so less torque goes into overcoming this friction, and more torque goes into tensioning up the bolt which provides the clamping force.

The more tension that goes into the bolt, the closer you get to the yield point.

As a rough guide, adding a lubricant to the thread can reduce the frictional losses by up to 30-40%, and unless you reduce the torque being applied to compensate, this means you are adding more tension to the bolt itself.

You can recalculate the correct torque if you know the material specs and expected coefficient of friction. But very important to know the original grade to determine how close we are to the yield point before a lubricant is added.

Engine oil reduces the frictional losses the most (and we know a little bit of oil covers a large area), but some anti-seize products reduce friction less and are better suited.

If you do add a “little bit of lubricant”, I would probably just drop the torque to 120Nm.

Edit: and I have to stress - this is only an issue if the original studs are grade 8.8. If the original studs are grade 9.8 or 10.9, then 140Nm is well below the recommended dry torque.

[ramblingboy42]

you can buy a dry spray-on molybdenum sulphide lubricant which works a treat.

I think you can get it from caterpillar or crc outlets.

[DiscoDB]

you can buy a dry spray-on molybdenum sulphide lubricant which works a treat.

I think you can get it from caterpillar or crc outlets.

Just remember they are designed to significantly reduce the frictional losses and increase the clamping force in high load applications.

The technical data sheets will normally provide the new K factors to use to recalculate the reduced torque settings to use to prevent over torquing the bolt.

You will find though they are not intended for use on wheel nuts.

[loanrangie]

Like Paul says, here we go.....

D2s have the same issue. I don't oil the threads, and have never seen the practice*, but I def use anti seize between the wheel boss and the hub, and the outside of the nuts.

* Not saying it's wrong, Ron.This is the only method I have ever used, never had a broken or siezed stud ever.

[DiscoDB]

Using a few drops of oil on wheel nuts is a practice commonly used in the trucking industry, primarily to overcome increased friction from dirt and minor damage.

[loanrangie]

Using a few drops of oil on wheel nuts is a practice commonly used in the trucking industry, primarily to overcome increased friction from dirt and minor damage.

I clean them if there is any crap on them.