My 21 Mazda CX5 came with 21mm lug nuts. My snow tire wheels came with 19mm lug nuts (it would be impossible to use the 21's on the snow tire wheels due to clearance issues). I was wondering if I could use the 19's on my stock rims. They seem to fit fine and actually look better than the stock lug nuts. The angled seats on both lug nut sizes appears to be the same which I assume would be the key criteria to interchange the 19's for the 21's. Am I missing anything else?
Dumb lug nut question
- Thread starter GaryMX5
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- Jun 2, 2002
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It's not a dumb question. The critical function of the lug nuts will be the seat design and the thread dimension. If your 19mm lug nuts are a conical seat design with a thread dimension of M12X1.5 then you can use them, provided they sit in the wheel recess completely.
Make sure you have an appropriate spare tire wrench.
FowVay answered the technical part completely correctly.
As a matter of naming, we don't generally refer to the head size when naming fasteners, even though it's often done. They should be referred to by their thread diameter and pitch.
FowVay answered the technical part completely correctly.
As a matter of naming, we don't generally refer to the head size when naming fasteners, even though it's often done. They should be referred to by their thread diameter and pitch.
I've had both 19 and 21 mm sockets and a breaker bar in the spare tire well for a couple of years now. I dislike the stock lug wrench that comes with most cars as it's often hard to get good leverage with them.
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Whata relief. I thought this thread was going to be about me.
I inherited the snows and lug nuts from my son when he moved to Texas. He had a CX5 as well. I used the snows with the smaller lug nuts for 2 seasons now. When I was switching out the tires and wheels last week I asked myself whether I could use the 19's with the stock rims but thought I should double check before doing so. As I said, the seats appear to be the same but I will measure the outside diameter of the seat to make sure.
Be sure and carry 5 Oem lug nuts for the spare tire when running snows if they aren’t the same lug nuts.
Thanks for the heads up. I think I'm ok, but will check to be sure.
I bought 19mm conical tapered lugs for my Accord summer rims. The rims are from a Hyundai and had 21mm head on them. For my lug wrench and jack it's 19mm factory.
I had to get the conical taper as the factory Honda ones have a ball seat on the lug. I have the opposite set in a box by the tires depending on season. Yes I have 5 spare factory ball versions for if I have a flat. I bought a set of Koken impact sockets with the protector on them. They fit in all my rims. That must be a very small lug nut opening or large sockets.
I had to get the conical taper as the factory Honda ones have a ball seat on the lug. I have the opposite set in a box by the tires depending on season. Yes I have 5 spare factory ball versions for if I have a flat. I bought a set of Koken impact sockets with the protector on them. They fit in all my rims. That must be a very small lug nut opening or large sockets.
Sage advice. A couple of years ago, Discount Tire convinced me to replace the lug nuts on the Sonata because the factory originals were starting to swell and causing problems getting the wheel off. A day or so later it hit me - what if the new lugs are a different size than the originals? Sure enough, the OEM lug wrench was too big to remove the new lug nuts.
Now I have one of these in the trunk:
Always run the same lug nuts.
Go with the 19mm and toss or give away the 21mm ones.
Cause what will happen is you'll forget the 21mm is on there and all you'll have is a 19mm lug nut removal tool. Or vice versa.
I have a 19, 21mm, and breaker bar in my car tool kit. It offers much better leverage than the stock lug nut wrench.
