Herald wheel nut thread size?

[jagnut66]

Hi, 

Just a quick question here, in case I have to recut the thread on the stud which secures my spare wheel in position in the well, what is the thread size of Herald wheel nuts?

Many thanks,

Mike.

[andybeau]

3/8" UNF is I remember correctly

[Pete Lewis]

Andy  you remember correct 

 all small chassis cars are 3/8" x24 unf   wheel studs @   38/ 42lbft MAX

being quite small dia.  is  so easy for a gorilla to strip them  and old tired studs fracture  

hence many move to 7/16unf ( ie big saloons)  or 12mm  landrover/ford etc 

Pete

 

[jagnut66]

On 31/07/2021 at 14:00, Pete Lewis said:

wheel studs @   38/ 42lbft MAX

That seems a rather low torque for wheel nuts?

Best wishes,

Mike.

[PeteH]

7 hours ago, jagnut66 said:

That seems a rather low torque for wheel nuts?

Best wishes,

Mike.

Haynes, Quote exactly the same. 38-42lb/ft. The Thread is 3/8UNF. BTW. I ran a Tap through some yesterday. Checked a couple of Supplier sites, the max recomended is no more than 48Lb/ft, for a Grade 5 Bolt/Nut. Like yourself, when I first saw it I thought it was a low figure.

Pete

[jagnut66]

Fair enough, I would have needed to know this soon anyway, for when I take my wheels off to change the tyres, so it's good (if a little surprising) to know.

Best wishes,

Mike.

[Pete Lewis]

10 hours ago, jagnut66 said:

That seems a rather low torque for wheel nuts?

thats exactly why so many get stripped or shear off completely  

and why many upgrade to 7/16unf or 12mm studs   you wont shear them 

bear in mind the std torque for a 3/8unf bolt is around 31lbft  so you are already  on higher grade steel studs and nuts for the 38/42 

but any done to a more average 60 will end up on the floor or you loosing a wheel  ...not a good experience 

these design torques are there for a very good reason 

Pete

 

[68vitesse]

Thought I read somewhere that aluminium wheels need a different torque setting to steel.

Or am I just dreaming.

Regards

Paul.

[Pete Lewis]

i would think alloy may deform if there any fretting going on as its softer?  than a steel wheel 

most with allloys up the stud size so that would allow a  higher torque but the stud thread form and nut are the limiting factor 

as most alloy's have a thicker nave  so  need  a longer stud so they up to the 7/16" or M12  studs then 65lbft   is more normal 

Pete

[Patrick Taylor]

I had new tyres fitted on Saturday: I asked the fitter to tighten the wheel nuts by hand and not with the windy wrench. The fitters were amazed to hear that the nuts should be torqued at 40lb/ft: they were doing vans at 170lb/ft! Would have stripped the nuts in seconds, I imagine....

[PeteH]

Pity the poor tyre fitter in a Truck Bay then. 400 to 450Lb/Ft and 10 Nuts per wheel. When I did a bit of LGV work, you always knew when the truck had been for service, Because the scheduler would leave the Torque Wrench, 5ft long and heavy, across the driver seat, your job then was to go round all the wheels, 4 or 6, and check torque all the nuts. If you got the 3 axle, It was 60 nuts to check!. ☹️ It was your responsibility if a wheel came off, no one elses.

Pete

[Pete Lewis]

or an 8x4   4 axle  and 80 nuts      

had a torque meter for checking production... looked   more like a parking meter up to 600 lbft   yes took some wielding 

always gave the audit task to the strongest  ,   anyone weedy couldnt hack it 

Pete

[PeteH]

On 03/08/2021 at 09:23, 68vitesse said:

Thought I read somewhere that aluminium wheels need a different torque setting to steel.

Or am I just dreaming.

Regards

Paul.

True in 90%+ of cases. Usually the torque for Alloy wheels is Lower. IE: My Motorhome, Sprinter based, has alloy wheels, the torque Figures for those is 240Nm (177Ft/lb) for Steel rims, and 180nm (133Lb/Ft) for Alloy.

I would guess, with no "factory" figure to fall back on. that 38 to 40Ft/lb would be OK? for Alloy`s on a Herald or Vitesse. OR whatever the alloy wheel supplier sugested if buying new.

Pete

[68vitesse]

My modern with ally wheels 120nm about 88ftlb, Vitesse steel wheels 38-42ftlb, numbers from handbook and WSM.

Regards

Paul.

[jagnut66]

On 08/01/2024 at 13:04, Patrick Taylor said:

I had new tyres fitted on Saturday: I asked the fitter to tighten the wheel nuts by hand and not with the windy wrench. The fitters were amazed to hear that the nuts should be torqued at 40lb/ft: they were doing vans at 170lb/ft! Would have stripped the nuts in seconds, I imagine....

Glad I read this, otherwise I might have found out the hard way. I may get a spare set for when I need new tyres, then fit them to Hetty myself after the new tyres are fitted to them.

I find it useful to have a spare 'slave' set of wheels anyway.

Best wishes,

Mike.

[GrahamB]

I just removed the wheels, put them in the back of my wife's car and delivered them to the tyre fitters.  That way I was sure the wheels would be fitted correctly once  I returned home.  You just need enough axle stands.

[Peter Truman]

You have to be even more careful if you have a Dolly Sprint with the alloy wheel nuts easily stripped with a rattle gun, the early models only had the 3/8in stud later increased to 7/16in, as the earlier ones were known to shear with enthusiastic cornering.

[PeteH]

A Lot will have to do with the quality of steel used in the manufacture of NON O/E studs. The strength of any threaded component is limited by the dia of the bottom of the thread which in the case of a 3/8" "bolt" is of the order of 0.06sq inch. Not a large cross section to resist the forces normal to driving, and which would be degraded further should the bolt be overstressed by overtorqueing, especially if it takes it beyond the "elastic limit" after which the bolt never returns to original length and the dia is "waisted" making failure even more likely. In essence, once a bolt/stud is overstressed it should be in reality replaced.

Uncle Pete, has advocated that if studs are replaced, serious consideration be given to upgrading, the use of land rover? studs (12mm?) Is I think the option. On balance I would definitely agree.

Pete

[Pete Lewis]

if you want to keep unified then TR/big saloon studs are 7/16UNF are also a direct fit 

in the small chassis hubs .

some use a ford 12mm    the choices are quite wide 

uncle bl**dy Pete 

 

[Patrick Taylor]

What I have found to be really poor are the aftermarket chrome wheel nuts sold to fit alloy wheels. The threads strip far more easily than on the studs, which is as it should be, of course: all engineering is predicated on having a hard material in contact with a (comparatively) softer/more elastic one. I keep a spare set of nuts to top up the set in use as they strip. And yes, I only torque them to 40 ft/lb.

[Gully]

5 hours ago, Patrick Taylor said:

What I have found to be really poor are the aftermarket chrome wheel nuts sold to fit alloy wheels. The threads strip far more easily than on the studs, which is as it should be, of course: all engineering is predicated on having a hard material in contact with a (comparatively) softer/more elastic one. I keep a spare set of nuts to top up the set in use as they strip. And yes, I only torque them to 40 ft/lb.

That's my experience too.

Gully

[Patrick Taylor]

18 hours ago, Gully said:

That's my experience too.

Gully

You have my sympathies. Disappointing, isn't it? 

Edited January 18 by Patrick Taylor
Typo

[Gully]

3 hours ago, Patrick Taylor said:

You have my sympathies. Disappointing, isn't it? 

And irritating!

Gully

[PeteH]

An update of sorts on this, I had the rear wheels off my 13/60, in the last week or so for access. Refitting yesterday, I found one of the Wheel nuts to have a noticably different Nose angle to the others. rummaging through my box of "spare wheel nuts various" I discovered a suitable nut Taper/thread wise, which was not 11/16 AF more 21mm? Eventually the stash did produce a correct nut. Worth watching out for, as the wrong taper could be a factor with wheels coming loose? 

Pete