# Wheel nut size?



## GMJ

Hi



I am looking to buy a torque wrench buy want to make sure I have the correct size. Could anyone advise the wheel nut size in inches/Msize/millimetres?



I have a 58 plated Bessacarr E795 on a Fiat Ducato base



Thanks



Graham


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## listerdiesel

I'd be surprised if it wasn't 19mm / 3/4".

But, looking on the web, 21mm seems to be the size for the bolt head:

21mm Head Size
16mm Thread
25mm Length of Thread
Fiat Part No: 1351203080
to fit:
Fiat Ducato all models (from 2006 on)

http://www.ricambio.co.uk/1806-wheel-bolt--fiat-ducato

Alloy wheels usually have different nuts, but I think the heads would be the same.

Peter


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## GMJ

Hmmmm...19mm or 21mm...that is the question!?!:smile2:


19mm as you say is 3/4inch which would be good/standard


Graham:smile2:


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## GMJ

They were 2 quid each so I bought a 19 and a 21mm in the end


Just in case....


Graham:smile2:


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## deefordog

The bolts on our 16" Kontiki rims are 21mm across the flats. I know this for certain as have just fitted some nut covers.


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## GMJ

Cheers


Im glad I bought the 19 and 21mm then:grin2:


Graham:smile2:


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## listerdiesel

That's interesting, we have studs on the Mercedes, 6 of them but the nuts are 19mm across flats. Studs must be 14mm.

Peter


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## HarryTheHymer

Am I missing something on this thread ?

The OP wants to purchase a torque wrench for the main reason of tightening up wheel nuts. 

All the torque wrenches I have purchased just have a square end bit and you then purchase a socket to suit. 

If the OP looks in his box which contains the vehicle jack he will see a wheel nut wrench. Take this to Halfords (or equivalent) and buy a socket of this size - preferably a socket with just 6 sides. 

The wheel nut torque on a 16" Fiat wheel is 180Nm (or 133 lbs ft in old money). So, the torque wrench needs to have at least that capacity.

Perhaps the OP wants to purchase a purpose made tool specifically for wheel nuts. I don't know.


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## listerdiesel

He wanted to know what socket size the wheel bolts were, as he had to buy a socket to fit.

Peter


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## Techno100

HarryTheHymer said:


> Am I missing something on this thread ?
> 
> The OP wants to purchase a torque wrench for the main reason of tightening up wheel nuts.
> 
> All the torque wrenches I have purchased just have a square end bit and you then purchase a socket to suit.
> 
> If the OP looks in his box which contains the vehicle jack he will see a wheel nut wrench. Take this to Halfords (or equivalent) and buy a socket of this size - preferably a socket with just 6 sides.
> 
> The wheel nut torque on a 16" Fiat wheel is 180Nm (or 133 lbs ft in old money). So, the torque wrench needs to have at least that capacity.
> 
> Perhaps the OP wants to purchase a purpose made tool specifically for wheel nuts. I don't know.


With you there, I was about to post the same until I read your post.


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## 747

I hope the OP realises that he will also need some way of loosening off the wheel nuts. It sounds like he is expecting to use the Torque Wrench as a general purpose tool for this.


This is not what they were made for. I have a 3/4" Drive Tommy Bar and Impact Socket for the wheel bolts on my 16" wheels.


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## listerdiesel

I would think he has, Cabby, the original requirement was for the size of the bolt head so he could get a socket for the torque wrench.

Peter


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## erneboy

Must say I read the OP as though the poster thought torque wrenches came is particular sizes. And for all I know perhaps some are made that way, though I've never seen such a thing.


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## Al42

"I am looking to buy a torque wrench" from the OP


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## HarleyDave

747 said:


> I hope the OP realises that he will also need some way of loosening off the wheel nuts. It sounds like he is expecting to use the Torque Wrench as a general purpose tool for this.
> 
> This is not what they were made for. I have a 3/4" Drive Tommy Bar and Impact Socket for the wheel bolts on my 16" wheels.


My torque wrench has the 1/2" drive shaft which can slide out to one side or the other so I can use it to tighten or loosen

Why shouldn't I do this?

Cheers

Dave


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## 747

HarleyDave said:


> My torque wrench has the 1/2" drive shaft which can slide out to one side or the other so I can use it to tighten or loosen
> 
> Why shouldn't I do this?
> 
> Cheers
> 
> Dave


Because in Engineering terms, a Torque Wrench is a precision instrument, not a general tool for slackening and tightening bolts. They need to be checked and calibrated at regular intervals (depending on usage), otherwise they are inaccurate and just another adjustable spanner.

Next time you board an aeroplane, just hope the Engineers were properly trained in how to use a Torque Wrench. :laugh:

As for your Torque Wrench being reversible, there are such things as bolts with a left hand thread.


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## HarleyDave

Oh - OK

I had thought that, because once the wrench had "clicked" at the preset value, it then "locked up" and became effectively solid.

I can see the issue with the old type which had a bending bar and a static needle but with the modern vernier type I thought I'd be OK

It'd be interesting (to me) to find out...

1 - how many people on here have a torque wrench

2 - how many actually use it to check wheel nuts etc

3 - how many have used it to undo fasteners

Cheers

Dave


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## HarleyDave

747 said:


> As for your Torque Wrench being reversible, there are such things as bolts with a left hand thread.


Do I detect just a trace of smug there?

"there are such thngs" - Puleese

And - isn't doing up a LH thread the same as undoing a RH thread??

Cheers

Dave


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## listerdiesel

We have a few, up to 3/4" drive, but rarely use it for tightening or checking wheel nuts, I prefer to use my own sense of 'feel', which has served me well over 50+ years.

Torqueing is fine under ideal conditions, but when the threads are dirty or corroded, those figures go out of the window.

For those without mechanical knowledge or skills, a torque wrench is a good tool.

Peter


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## HarryTheHymer

listerdiesel said:


> Torqueing is fine under ideal conditions, but when the threads are dirty or corroded, those figures go out of the window.
> 
> Peter


You could put a very small amount of copper grease on the threads - Oh no, I've opened up another can of worms :surprise:

SORRY


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## listerdiesel

I am a firm believer in the use of Copaslip, on steel wheel threads and centres as well as alloys.

Never had any problems and the threads are always undamaged after removal.

Peter


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## 747

I am the same as Peter, I can get pretty close to the Torque figure if I know the length of the Tommy Bar and know what weight I am. :smile2:


I also use Copperslip even though I have read on motorhome forums that it should not be used. I personally think that advice is wrong.


If anyone uses a Torque Wrench for undoing bolts then good luck to them, they paid the money to buy it and are entitled to use it as they wish. :smile2:


BTW, torqueing up a LH thread IS different to undoing a RH threaded bolt. The bolts used on wheels are a high tensile bolt, not a mild steel bolt. They screw into a mild steel hub (sometimes a mild steel forging) and therefore 'bite' when a lot of pressure is applied. if you tightened to let's say 150 ft/lb, it would take a little more than 150 to loosen the bolt. You might have come across this factor when loosening off Cap Head (Allen) bolts. They need more effort to 'crack' loose than when they were tightened.


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## BillCreer

listerdiesel said:


> I am a firm believer in the use of Copaslip, on steel wheel threads and centres as well as alloys.
> 
> Never had any problems and the threads are always undamaged after removal.
> 
> Peter


Don't agree Peter. Lubricating threads distorts any reading and feel when tightening. Most torque readings, on wheel nuts, are given for dry clean threads as lubricating will lead to over-tightening.:nerd:


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## GMJ

Hi all

I have bought a torque wrench and was after the size of socket to go with it. Due to conflicting advice/reports I bought a 19 and a 21mm. They were 2 quid each so no dramas!

I carry a jack and brace set with me which I will use for general untightening and tightening. The torque wrench will be used to ensure that I am at 180NM. When I recently had my tyres changed the chap did them to 220NM as he/I didn't know the correct rating.

I have just had my full service and was advised to check all wheel nuts after 30km of driving as the wheels had been removed for the brake check. I have checked them but just with the wheel brace which is why I decided to buy a torque wrench as I don't have one.

I am also in the process of buying and will be installing, a spare wheel. Therefore it makes logical sense to me to carry a torque wrench in case I need to use the spare wheel.

I could have taken my wheel brace from the MH and then taken it to Halfrauds however I see little reason to do this when there are folks like you (and the Swift owners forum) who can furnish sensible replies.

Thanks all

Graham


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## listerdiesel

BillCreer said:


> Don't agree Peter. Lubricating threads distorts any reading and feel when tightening. Most torque readings, on wheel nuts, are given for dry clean threads as lubricating will lead to over-tightening.:nerd:


Bill:

Show me a used vehicle that has dry and clean threads?

Doesn't happen in real life, the threads get corroded and dirty with brake dust and road muck, which is just as bad if not worse than having them lightly lubricated.

Threads gall and bind when dirty and start to tear the thread up, that never happens on my wheels, but I've seen plenty on which is is only too obvious.

What ever happened to the checking of wheel nuts regularly? How many do that now, not many I'll bet.

Peter


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## peejay

On a previous van we had alloys fitted and a steel spare, each had a different socket size.

I bought a telescopic wrench with double sided sockets similar to this...

http://www.ebay.co.uk/itm/New-Telescopic-Extendable-Wheel-Brace-Wrench-2-sockets-for-17mm-19mm-21mm-23mm/121535251134?_trksid=p2054897.c100204.m3164&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140407115239%26meid%3Da42bccd34dcc4415acbd97b7635f98ce%26pid%3D100204%26rk%3D3%26rkt%3D30%26sd%3D351198852295

Always carried one ever since instead of that blooming great thing supplied by Ducato.

Just saying :wink:

Pete


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## BillCreer

listerdiesel said:


> Bill:
> 
> Show me a used vehicle that has dry and clean threads?
> 
> Doesn't happen in real life, the threads get corroded and dirty with brake dust and road muck, which is just as bad if not worse than having them lightly lubricated.
> 
> Threads gall and bind when dirty and start to tear the thread up, that never happens on my wheels, but I've seen plenty on which is is only too obvious.
> 
> What ever happened to the checking of wheel nuts regularly? How many do that now, not many I'll bet.
> Peter


Peter this is extract from a chart which shows how to make allowances for different coatings.

*LUBRICANT OR PLATING...............TORQUE CHANGES*
Oil...............................................Reduce torque 15% to 25%
Dry Film (Teflon or moly based)......Reduce torque 50%
Dry Wax (Cetyl alcohol) ................Reduce torque 50%
Chrome plating............................. No change
Cadmium plating................... ........Reduce torque 25%
Zinc plating....................................Reduce torque 15%

My nuts are always clean and If I'm in the mood I give them a quick rub with a wire brush.:wink2:


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## listerdiesel

BillCreer said:


> My nuts are always clean and If I'm in the mood I give them a quick rub with a wire brush.:wink2:


That sounds spectacularly painful, Bill! :grin2::grin2:

Peter


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## BillCreer

listerdiesel said:


> That sounds spectacularly painful, Bill! :grin2::grin2:
> 
> Peter


Beats dangling them in a cleansing agent.


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## GMJ

Update


I got my torque wrench and 2 sockets: the bolt heads are 21mm as generally suspected.


Job jobbed!


Cheers


Graham:smile2:


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