Rationale for Left Handed Lug Nuts?

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w30bob
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Rationale for Left Handed Lug Nuts?

Post by w30bob »

Hi Guys,

Today I took the front wheels off my M to grind off some snow plow mounts the previous owner welded to the frame. He actually welded the driver's side mount, made of C-channel directly over the truck SN stamped in the frame........but luckily the welds didn't contact the numbers. So I take off the passenger side wheel easy enough, remove the mount, and start on the driver's side. Damn those lug nuts are tight!! Like way too tight! Then I remember seeing ads on Ebay for Budd wheel lug nuts and something stated about left and right threads. You know where I'm going with this........so I try turning them the other way. BINGO....they came off. And of course when I looked at the lugs it says right on there "left". Remember, this is my first military vehicle....so no laughing. Ok...go ahead and laugh...it was a bit funny watching me wrenching on that lug wrench.

So now I'm wondering why exactly did the military use both left and right hand threads on lug nuts? Just to mess up drunk G.I.'s who had to change a flat on the way back from the bar? I'm not thinking of any obvious good reason for such a thing. But I'm sure you guys know. So let me in on the secret. :o)

regards,
bob
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Re: Rationale for Left Handed Lug Nuts?

Post by WarrenD »

It wasn't a military thing, it was Chrysler. The theory was, as the wheel rotated the lugs on the left side would loosen if they were right hand thread. If they were left hand thread, they would tend to tighten as the wheel rotated and thus not fall off. This was common practice with MOPARS into the early 70's IIRC.
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Re: Rationale for Left Handed Lug Nuts?

Post by w30bob »

Thanks Warren. You gotta love Mother Mopar!

regards,
bob
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Re: Rationale for Left Handed Lug Nuts?

Post by Glenn »

It was actually more than just Chrysler, left hand lug nuts have been around for a long time. Willys Jeeps were that way also, along with other makes as far as I know.
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Re: Rationale for Left Handed Lug Nuts?

Post by skinnedknuckles »

Budd wheels on semis and dump trucks were also left hand thread on left side and right hand on the right side
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Re: Rationale for Left Handed Lug Nuts?

Post by k8icu »

It was a common automotive practice for many many years. Both small vehicles and with big rigs. Some commerical trucks still use the left right thing. My M211 2.5 tone had left hand threads, but I don't remember if the M35a2 did. Guess I didn't take the wheels off that truck as much as I did on the old GMC. Now my M151 was regular right hand threads all around.

Don't feel bad Bob, I think we've all done that at one time or another. And yes I've seen drunk MV oweners try to take the drivers side lugnuts off...it is funny!
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Re: Rationale for Left Handed Lug Nuts?

Post by MSeriesRebuild »

k8icu wrote:It was a common automotive practice for many many years. Both small vehicles and with big rigs. Some commerical trucks still use the left right thing. My M211 2.5 tone had left hand threads, but I don't remember if the M35a2 did. Guess I didn't take the wheels off that truck as much as I did on the old GMC. Now my M151 was regular right hand threads all around.

Don't feel bad Bob, I think we've all done that at one time or another. And yes I've seen drunk MV oweners try to take the drivers side lugnuts off...it is funny!
Yep, the M35's and the 5-tons are that way also.
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Re: Rationale for Left Handed Lug Nuts?

Post by Tanner »

Left-hand threads deters tire thieves... on one side of your vehicle. :D

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Re: Rationale for Left Handed Lug Nuts?

Post by w30bob »

That would explain why I only see the right side tires and rims for sale! :o)

regards,
bob
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Re: Rationale for Left Handed Lug Nuts?

Post by Wayne64 »

Funny this thread should pop up now. Trust me I'm not looking for a buyer but I'm finally selling the last of my LH nuts (1/2-20) I got tired of trying to screw them onto a RH stud :oops:
http://www.ebay.com/itm/330761839675?_t ... IT&vxp=mtr

Short story: back in 1970 I was an apprentice Steamfitter. The journeyman always had fun with us newbees by handing us either an elbow or coupling that was a left hand thread and watching us try to catch it. FYI left and right elbows, nipples and couplings were common before ground joint unions were used.
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hbb
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Re: Rationale for Left Handed Lug Nuts?

Post by hbb »

This practice started with the earliest wheeled wagons and machines that used threaded fasteners.

hb
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Re: Rationale for Left Handed Lug Nuts?

Post by Rusty1340 »

We use to have a lot of fun in the day watching the younger hobbist fight with LH lugs. When I was doing my Willys the LH lugs brought back some memories of working in the shop with my dad, him watching me fight with and old Chrysler. I sure miss him
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