Wheel bolts torque settings.

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Or for you oldies out there ...

110 Nm = 81 lb.ft
150 Nm = 110 lb.ft
130 Nm = 96 lb.ft

REGARDS

Phil

That was kind of you to do that, thank you from an oldie
 

Midland45

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Just one point to note on torque settings. Most are quoted for dry bolts, ie those that have not had any grease applied to the threads. A greased bolt will be tightened more for the same torque setting.
 

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Did some research on this and there seems to be two schools of thought. From another site
"Strictly speaking the wheel bolts should be installed 'dry'. Nowadays, though, wheels can stay on the car for literally years without being removed - hence problems with alloys 'welding' to hubs and wheel bolts siezing. What I do is put a little copper grease on the contacting surfaces and also a smidgeon on the threads. I don't lubricate the bevel that locates the bolt in the wheel. I then use a torque wrench and tighten them to the bottom end of the specified torque range. I've never had a problem doing this on numerous cars in the best part of 30 years.
 

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Tiny bit on the thread is ok, but as you rightly said, on the bit that grabs the wheel itself must be dry!!
 
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Did some research on this and there seems to be two schools of thought. From another site
"Strictly speaking the wheel bolts should be installed 'dry'. Nowadays, though, wheels can stay on the car for literally years without being removed - hence problems with alloys 'welding' to hubs and wheel bolts siezing. What I do is put a little copper grease on the contacting surfaces and also a smidgeon on the threads. I don't lubricate the bevel that locates the bolt in the wheel. I then use a torque wrench and tighten them to the bottom end of the specified torque range. I've never had a problem doing this on numerous cars in the best part of 30 years.

That is fair comment, and nothing wrong with doing that:D
 

turbopete

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when i was going through college serving my apprenticeship i was always told to install nuts/bolts DRY. worst case scenario, a little wd40 but NOT recommended as ANY lubrication makes the bolts/nuts artificially free on the threads so when the torque wrench says its at the correct torque it CAN be significantly over! yes copper grease on the contact surfaces is a good idea, and no harm in it. personally id stick by what i said earlier in the thread and NEVER lubricate the nuts/bolts. you may not have had any problems but most people dont tend to use a torque wrench, tighten the bolts/nuts, end up with them overtightened and next time the car is in for service they can be pigs to remove as ive seen studs stretch etc before now! many people believe tighter is better. this is completely wrong! thats also why id never lube wheelstuds/bolts. ive seen extremew cases where people have overtightened wheelnuts and the wheel has later come off! how? simple. overtightened nuts, stretched studs, stretched studs end up snapped and wheel overtakes you!
 

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They should be dry.

The root of the problem is that, despite using a fancy piece of kit, tightening a fastener to a specified torque is a truly awful installation method.

The purpose of tightening a bolt is to elastically (and in some cases plastically) deform the bolt, to stretch it. For equilibrium, the stretch in the bolt is matched by the compression across the faces of the joint.

In the case of a gasket joint, this compression is needed to make the gasket seal.

In the case of a wheel to hub joint, this compression is needed to transmit the drive and brake torque. In this respect, the hub face and inner face of the wheel are acting as the two faces of a clutch. The bolts themselves should not be transmitting the drive and brake torque.

So, applying torque to stretch and preload the fastener is how it tends to be done, but, it's a rubbish method. It's poor because there is so much variation in the levels of inter-thread friction, and friction between the bolt head and clamped part (in our case on the radius under the bolt head).

During some tests I did on a rail vehicle, with instrumented M16 bolts, after torquing using a calibrated torque wrench, wielded by a highly trained fitter, there was of the order of 25% scatter between the bolt which was stretched the most, and the bolt which was stretched the least.

Using grease anywhere on the bolt is a bad idea, becasue you then get more stretch of the bolt for your torque, and you are over-stressing the bolt. However, as the under head (or radius) section is at a larger radius from the centre line of the bolt, changing the friction here has a larger effect on the torque to preload conversion.

Using grease on the wheel to hub joint face is also a bad idea, because this face transmits the drive and braking torque. Some calculations I did demonstrate that you would get slip across such a grease joint under hard braking conditions.

Slip across the wheel and hub interface is bad because this loads the bolts in a way they were not designed for.

If you are concerned about alloy to hub corrosion, it's better to remove wheels frequently, perhaps as part of a rotation regime, and clean thoroughly.

It happens that manufacturers have long known about the abuse meted out to wheel bolts, and they tend to be designed with a large margin of safety or margin for bodging!, and so people tend to get away with it.

On commercial vehicles, the design margins are not so large, and wheel loss is much more common.
 

euclidb2

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wheel bolts

To be honest over the past 40 odd years i have always put a bit of vaseline on the bolts when i have removed them for any reason,just recently i changed my wheels over .....i have two sets.....and stripped the threads on two bolts........never owned a torque wrench...........actually it put a little smile on my face,not bad for a 61 year old i thought,bolts were £2.50 each so not too bad.........:)
 
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To be honest over the past 40 odd years i have always put a bit of vaseline on the bolts when i have removed them for any reason,just recently i changed my wheels over .....i have two sets.....and stripped the threads on two bolts........never owned a torque wrench...........actually it put a little smile on my face,not bad for a 61 year old i thought,bolts were £2.50 each so not too bad.........:)

You are eating too much spinach
 

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Vaseline

To be honest over the past 40 odd years i have always put a bit of vaseline on the bolts when i have removed them for any reason,just recently i changed my wheels over .....i have two sets.....and stripped the threads on two bolts........never owned a torque wrench...........actually it put a little smile on my face,not bad for a 61 year old i thought,bolts were £2.50 each so not too bad.........:)

Try Aloe Vero on your face, it's non-greasy. Have never tried it on nuts though.

REGARDS

Phil
 

type49

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They should be dry.

The root of the problem is that, despite using a fancy piece of kit, tightening a fastener to a specified torque is a truly awful installation method.

The purpose of tightening a bolt is to elastically (and in some cases plastically) deform the bolt, to stretch it. For equilibrium, the stretch in the bolt is matched by the compression across the faces of the joint.

In the case of a gasket joint, this compression is needed to make the gasket seal.

In the case of a wheel to hub joint, this compression is needed to transmit the drive and brake torque. In this respect, the hub face and inner face of the wheel are acting as the two faces of a clutch. The bolts themselves should not be transmitting the drive and brake torque.

So, applying torque to stretch and preload the fastener is how it tends to be done, but, it's a rubbish method. It's poor because there is so much variation in the levels of inter-thread friction, and friction between the bolt head and clamped part (in our case on the radius under the bolt head).

During some tests I did on a rail vehicle, with instrumented M16 bolts, after torquing using a calibrated torque wrench, wielded by a highly trained fitter, there was of the order of 25% scatter between the bolt which was stretched the most, and the bolt which was stretched the least.

Using grease anywhere on the bolt is a bad idea, becasue you then get more stretch of the bolt for your torque, and you are over-stressing the bolt. However, as the under head (or radius) section is at a larger radius from the centre line of the bolt, changing the friction here has a larger effect on the torque to preload conversion.

Using grease on the wheel to hub joint face is also a bad idea, because this face transmits the drive and braking torque. Some calculations I did demonstrate that you would get slip across such a grease joint under hard braking conditions.

Slip across the wheel and hub interface is bad because this loads the bolts in a way they were not designed for.

If you are concerned about alloy to hub corrosion, it's better to remove wheels frequently, perhaps as part of a rotation regime, and clean thoroughly.

It happens that manufacturers have long known about the abuse meted out to wheel bolts, and they tend to be designed with a large margin of safety or margin for bodging!, and so people tend to get away with it.

On commercial vehicles, the design margins are not so large, and wheel loss is much more common.

Interesting reading that still has me a bit confused with regarding Loctite/thread-nut type products. These are sometimes recommended by the manufacturer during rebuilt but are surely acting as a lube when first assembled & still "wet", so, possibly overstetching the bolt/stud??
 
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Interesting reading that still has me a bit confused with regarding Loctite/thread-nut type products. These are sometimes recommended by the manufacturer during rebuilt but are surely acting as a lube when first assembled & still "wet", so, possibly overstetching the bolt/stud??

And why not indeed
 

Number_Cruncher

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Interesting reading that still has me a bit confused with regarding Loctite/thread-nut type products. These are sometimes recommended by the manufacturer during rebuilt but are surely acting as a lube when first assembled & still "wet", so, possibly overstetching the bolt/stud??

You are quite right to be confused - it's a bit of a minefield.

In testing I have done, using instrument bolts to measure the strain in the shank, some Loctite grades *do not* act as a lubricant, and can actually act to increase thread friction even while wet, which completely upsets the relationship between torque applied and axial load generated in the bolt. Loctite have recognised this (Many people before and since have done similar investigations), and have produced some grades which don't behave in this way.

For me, the approach I would follow is;

1) If I were designing a mechanical joint where I wanted to use a threadlock, I would insist upon testing it, perhaps using instrumented bolts, to see and understand the friction effect of the adhesive.

2) When using a bolted joint on a car with threadlock, I would follow the vehicle manufacturer's procedure, which would probalby include a thorough cleaning of all the threads, and the use of a prescribed amount of a prescribed grade of threadlock, followed by a prescribed installation procedure. You have to rely upon the design and development work done by the maker.

3) I would not, ever, begin to add threadlock to threaded fasteners in an ad-hoc manner, or on a whim, because I know I would be in danger of upsetting the way that the bolted joint works.
 

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Finally got around to reading this very informative thread and it brings 2 thoughts to mind:

1. Got to get myself a torque wrench as I have always used all my strength to tighten bolts thinking that is the correct approach (Worse, in the last few years I've been doing that while using an extending bar wrench!!!)

2. In the past I have used spacers on wheels (to stop rubbing on the inner arch). I thought they would be fine as I used extended length bolts when I fitted them. From what I have read on here they must be a really bad idea as they would stop\reduce the intended clutch effect between hub and wheel and place more reliance on the bolts to transfer the load. Especially as I used to liberally apply copper slip!

It just shows how a little knowledge can be dangerous.

Dave
 

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