Someone mentioned mopar sizes. Big cars were 1/2, small cars 7/16 in most years. LH on left side only
I bought mine at NAPA 1/2" 20 L to fit the '63 Pontiac rear in my current project. I will knock the studs out and replace with RH studs before it hits the road, seems kinda dumb to have left hand threads on only one wheel..
Well at least in Canada.... many dorman parts cross into Napa numbers. Always three digits, a dash and four digits. Here Napa puts their own number and logo on them. Sent from my iPhone using H.A.M.B.
When I worked at the Dodge dealership, guys uses to come in with 5 broken studs with the nuts still attached and the letter L quite visible on the end of the stud.
I had a '73 Plymouth duster in high school, it had the left hand lugs on the drivers side....my Dad made a special point of making sure I knew that. Had them up to '76, maybe later IDK on the Chrysler A- body....might have ended when the Aspens replaced the Duster/Valiant/Swinger
So, is it a failed concept, this left hand thing? I was putting the front wheels on my Chevy (rh thread) a few years ago. I got distracted, came out later, dropped it off the jack and drove off with the lug nuts hand tight. The driver's side wheel came off a couple miles later (passed me, went through a blackberry hedge and landed in a swamp). Wonder if left hand threads would have made a difference.
The original concept of the LH & RH thds was that they would be self tightening with the normal rotation of the wheels when driving down the road. Not tight tight but would keep them from coming off. They finally determined it really wasn't an issue if they were all RH as long as they were properly tightened. Even the Pontiac 8 lug aluminum hub and drum setup had LH thds up thru 63. Chgd to all RH in 64.
I hear just as many stories about guys not knowing they're LH and screwing things up, as I do about wheels falling off the left side of the car because they were loose. Using all RH keeps the part number count down. 56 plymouth is a good one...studs front, bolts on the rear, and they are LH and RH. So each wheel uses a different fastener!
I had a 56 Plymouth in about 1966 and yes now I remember the rear wheels having bolts. It never hit me before that all 4 wheels had their own fasteners.
My 59 Olds has left hand nuts on the left side and right hand nuts on the right side Sent from my iPhone using The H.A.M.B. mobile app
I remember doing a brake job on a Chrysler. left hand nuts on the right front, left hand nuts on the left rear. the last guy put the front hubs on the wrong side.
I saw that at least once back in my Firestone days. Still had my old impact wrench that didn't have much power so when it stalled out I started checking.