Just saw a random comment about LH thread lug nuts on one of the larger F series -- possibly a 350.

Seems to me that there was a theory that they'd self tighten -- when they were on the driver's side ( I believe).

Thought I'd ask who knows what vehicles used them and when they quit.

Mopar used them into the late 60's. I actually don't think that they changed until 1970. ( Most of the time they were kind enough to put an L in the wheel stud. )

Anybody know about some others.

 

my grandma's 78 volare had them,as I found out the hard way when I was changing a flat tire and couldn't get the lug nuts off

 

The only ones I have ever run across, were the police-issue Dodge Polara's back in the mid to late 60's and was a special-order item from the CHP, passenger side only. That was one sure tip-off to a true non-emmissions Cali big block Chrysler product. When you think about it, it really does make sense, until you try to do a resto on one.
I'm sure there were others, but I'd have to dig deep into my books. I bet NumberDummy could tell ya a lot more than us mere mortals. Didn't the Hudson Hornets have the left hand threads on the pass. side?


Pete

 

My 73 F-350 Tow truck has left hand threads on the drivers side.

 

Having no experience with the heavy Fords, I still just don't get it. Wouldn't you want the lugs to tighten in the opposite direction that the wheels roll? Left hand threads just happen to make sense to me on the pass. side only. I had to pound it into my crew that there was a reason why my knock off hubs were theaded opposite on the sprint car.


Pete

 

All the left hand lug nuts I've ever seen were on the left, or drivers side.....................

 

My '56 F350 has them on the Drivers side.

 

yep, i got those stupid left hand ones on my 68 coronet. i think it started as a chrysler thing. i had no idea when i first got it, whent to pull the tire and couldnt brake them loose. i had my longest breaker bar on them pullin as hard as i could, then my old man says "dont ya know yourt goin the wrong way".. i still forget half the time when i'm workin on it...

 

Some 80's 250's and 350's had them as well. My dad's 84 had them from factory, but the replacement rotors are not.

 

I had a 1941 Oldsmobile and it had left hand threads but I can't remember which side.

 

Did a little more surfing. Apparently, GM had them on some cars (Ponitac among others), through the 60's.

I guess there really was an issue with lug nuts loosening up. Don't know if the LH threads worked or not, but it was one attempt at a solution.

The 'fix' is the conical nuts that they use these days. The tapered part at the end of the nut must jam into the wheel so that the nut won't loosen.

 

We had a 55 Desoto that had the left hand thread. I don't remember which side it was on.

 

I drove a 1980 F-350 and it had left hand threads (driver's side if I remember correctly).

I remember them on the bigger vans too.

 

Yup, got em on the driver's side of my '82 E-350 dually motorhome. The L is there on the end of the stud, just hard to see with all the paint and rust. I hope I never lose the lug nuts.

 

I have never run into a left handed wheel stud on the passenger side of a vehicle. I ain't saying they didn't make any, I just never saw any. That would defeat the theory behind it though by putting them on the right side (passenger side) of the vehicle. The theory was, I believe, that the rotation of the wheels could loosen up the lug nuts on the drivers side, so they went with left handed lug nuts.

As for other vehicles, semi-trucks and dump trucks have been doing that for a long time too on their bud wheels. Bud wheels, AKA stud piloted wheels, have left handed studs on the left side. In fact, their duals have 20 lug nuts holding the wheels on. You have a thimble that goes on the stud holding the inner wheel on that has threads on the outside of it for the outer lug nut. The inner thimble is recognized by a 13/16ths square on the end for a 4 point socket. They do have an L or R stamped in the end to know the difference. These were used fairly regularly up until about 10 years ago. You can still get them that way if ordered. The main reason for doing that would be so you can use the same truck rims you already have without having to stock 2 different types of rims. What's fun is changing a tire and someone put a right handed stud in a hub on the left side and you don't know it until you break it off.

As for big trucks, the most common by far is the hub-piloted wheel today. The rim makes contact with the hub and carries the weight at that point. The 8 or 10 wheel studs only have to hold the wheel on. There are some out there that actually put bud studs in a uni-mount hub, there by getting the best of both worlds I guess. Since the hole in the center of the rims are the same, the bud wheels will fit on a uni-mount hub. But don't try putting uni-mount wheels on a bud wheel hub. That won't work.