Left hand threads

Hi,
I know it's probably an old (and dumb) question, but every now and then have come across left hand thread wheel nuts. Had a few early Jeeps where I first noted this and as I was in the process of doing them up, so simply pressed or punched them out and reinstalled all R/H threads all round with no obvious ill effects. A lot easier to get hold of , both studs and spare nuts readily available, plus also converted a few front ends to disc brake where a longer stud was necessary.
From what little I have seen, just about everything these days seems to use R/H wheel studs and nuts. So, the question is, why use L/H studs and nuts at all, on wheel fitment?
Someone or other reckons that it was a throwback to old military application, where anybody and everybody may have been thrown in as a driver if needed, and changing a flat was basic driver maintenance. I have a feeling that it may have pre-dated WW2, so probably not the correct answer. Would it have had anything to do with the way early wheels were mounted on the rim, where possibly the rough roads as well as the constant vibration may have loosened the actual studs with the possibility of dropping a wheel off? Seems to be a bit antiquated in this day and age, but perhaps there is still the odd vehicle being made who does stick to the old R/H and L/H wheel studs for rim mounting.
Just wondering,
Dave
I have come across L/H threads quite often, even in modern use, machine tools for example.

Cogz M80
Probly rong (again)

twaz told RH threads on the passenger side came loose from the wheels spinning in a anticlockwize fashon
so they fitted LH threads coz of the spinn anti C/W made keep tight

Butt
WaddaEyeKno

cya
§

Yep, that crossed my mind also, Swishy. Maybe also something to do with some rims being centred on the actual hubs but others being centred by the wheel nuts themselves, as in countersunk mounting holes with corresponding wheel nuts with a matching lip on them?
Bit of research put up by some Mopar bloke reckons that they (Chrysler) were still using them on passenger cars up until the 1970's simply because one of their component manufacturers ran off a million or so L/H thread wheel studs and nuts and they were simply using up old stock. Apparently they had been received by the different factories and by the time anyone twigged, the component manufacturer had already spent the cheque! Don't know about that, but feasible I suppose.
Dave

Our '29 and '38 Nash cars both have left hand threads on the left side with tapered locating nuts.
The Guy truck is the same, the inner dual sits on a locating rib on the hub against a tapered ridge on the bolts, outer dual depends on tapered nut as does the front wheel.
They all rely on the nuts, doesn't tell us why they did it.
Bit off topic, both right hand thread.
Our International AL 160's had five stud rims, one had the inner dual fitted first with the long tube nut, outer rim held on with nut screwed over tube, used to break bolts.
Other one had the tube nut screwed right on to the hub and both wheels held with outer nut, didn't break bolts.
David.

wouldyou,

Yes they are still about. The 4 x 4 Isuzu at my local Bushfire brigade (about 5 years old) has them.
The left side studs / tube nuts are stamped ' L ' on the ends
Same setup as the old inters. Never gives trouble but a PITA to change a tyre.

OK for me because I know what I'm looking at - being old and grey.
Not so easy for those who haven't seen such things .
They don't sell many 4 x 4 trucks so the old designs keep on & on & on. I'd be surprised if the latest model was different.

We've got a newer 4 x 2 which has normal studs/nuts.

Cheers from the oldb

Folks
Agree with Swishy #17738.
Poms , Chrysler cars and many Jap trucks had it for years.
Worked in tyre business in my youth.
Often see Valiants with a mix of LH and RH on one wheel- well meaning owners messed with it.
Fortunately for me the rattle gun never sheared any ....
How useful are those yellow pointy headed things?
You know-they aim at each other, so if a wheel nut loosens, you should see.
Was always a believe in the run around with the cheater bar after about 100 miles if tyres and wheels were messed with.
Riches garbos have another yellow type thing.
Saw them first in U.K. in the 80's-bought a few packs real cheap with a view to making a fortune in Oz.
Not enough contacts, nobody cared, and fortunately I wasn't out of pocket.
But I do wonder .......
Happy New Year

VP and all those old Dennings and Tourmasters running on Rockwell gear had LH 7/8 studs and nuts on one side.
As we needed longer for alloys they are now all RH 19mm metric, but the saga to get there is a tale in itself.

As a youngster I was told the LH thread wheel nuts on the left side was to stop them from undoing. Same story for the axle nut, left hand on the left end of the axle.
The only trucks I saw lose wheels were the early Euro stuff, Mercs etc that ran right hand threads on both sides.
Think the BPW axles also were RH on both ends as my brother-in-law was always chasing run away wheels on his BPW equipped dog trailer. But once you've run a steel wheel with loose nuts, she's buggered, tapered holes have gone from circles to ellipses.
Wobbly wheels went against that convention though, I never saw any LH thread on spiders.
Yes I can remember helping a lady change a flat left rear tyre on her early Valiant, left hand thread. Lucky I had eyes that worked back then.

I may be wrong,but weren't LH threaded nuts on the right hand side,or that is how I remember from all the pommie cars I came across in my younger days.. cheers Don

Left hand threads are used on dual wheel assemblies so the inner nut tightens while the outer nut loosens. This stops the stud from being trapped on the outer rim if the inner nut were to loosen.