Anybody have a metric socket wrench?

I’m not talking sockets- I’ve got metric ones in 1/4", 3/8" and 1/2" drive- but that’s the point- there are all fraction of an inch drive. Where the metric system rules are you getting a 4mm, 8 mm drive or whatever? I’ve not spent much time in hardware stores overseas but I can’t believe your choice in France or Russia is between 3/8" drive and 1/2". Any international gearheads out there?

Per Wikipedia: “…the ratchet, which comes in standard sizes of 1/4”, 3/8", 1/2", 3/4", and 1" (a de facto international standard with “no” metric equivalents)…

I assume the info is basically correct, even though this particular passage is not foot-noted.

Thanks. I guess I should have thought of using the Internet that way to get information.

Russia does have the metric crescent wrench :wink:

Occasionally, someone at work will jokingly ask if anyone has seen the metric fits-all…

Another odd leftover inch item - wheels. Except for some oddball Michelins from the '80s, all wheels, car and motorcycle, are in inches, aren’t they?

Great question. I’ve no doubt that Wikipedia is correct, English being the international language of business. Perhaps it all evolved from when England was the world’s superpower. No, wait, England is metric! Okay, I give up!

I’m still wondering why tires use metric section widths, diameter in inches, and a ratio for the sidewall height. Seems to be the height of illogical thinking.

Unless u got those darn Michelin pax tires. They are all metric designation.

I was thinking of their TRX tire/wheel. It was really an odd combination - Michelin TRX tires/metric wheels on the Mustang GT:

Read more about the TRX here:

I have metric ratchets, I have a 12.7mm, several 9.525mm and a couple of 6.35mm ratchets. I also have the corresponding torque wrenches for the 9.525mm and 12.7mm and one with a 19.05mm drive.

Yea…the ratchet size all seem to be in inches.

I thought I would have to buy a whole new set of sockets when metric came out. The biggest expense was the ratchet. But it was a nice surprise that I could use my existing ratchets and just get new sockets. I had just about a couple of Snap-on ratchets and didn’t want to go through the expense of buying new ones. I suspect that was a big driving force into why they didn’t make new metric ratchets.

Funny…is that spark-plug sockets are still SAE (lets not get into that discussion again). Our Honda’s, Nissans, Totoyta’s and Lexus all spark plugs were removed with either a 5/8" or 13/16" socket.

The transmission plug on my wifes Accords was 3/8" square. You just used a 3/8" ratchet. Fit PERFECTLY.

Another huge advantage to winning the big one…WW2 !

Ah, mustang turbo. I recall the 2.3 pushrod turbo, the svo turbo, which was nice. And the very rare turbo gt, which was the OHC 4cyl non inter cooler turbo motor. Well u could get the stang with a v8 too but turbo was the cool motor back in 1980.

I forgot about spark plugs. Are all cars pretty much 5/8" now? My last few have been. Still have a lawnmower that needs the 13/16".

OK, tire sizing:

Long version:

Short version:

Imbedded in the tire size is some additional information about the dimensions and the load carrying characteristics.

A few versions back in time, tire sizing looked like this: 8.00-15, which means the tire is mounted on a 15" wheel, and is 8.3" wide (on a 6L rim), and has an aspect ratio of 88%.

When it came time to change tire size, the Europeans took the opportunity to go metric, but they were stuck with the inch wheel size (with a few exceptions). The Americans changed tire sizing, too, but went a different direction. Which was OK because very few vehicles crossed the Atlantic.

Nowadays, tire sizing is quite a bit more standardized, but the old inch wheel thing has been carried over. Why? Because only 15" tires fit on 15" wheels and if they didn’t produce 15" tires, all the old vehicles with 15" wheels would not have tires available and would require everyone to buy new wheels. Very unhappy campers - as witnessed by the TRX problem mentioned above.

Back in the days of the TRX tire, car tires were pretty much limited to 13, 14 and 15" wheels and consumers wanted it to stay that way. Now we have tires in every inch size from 15 up to 22" along with 24 and 26". This might be a good time to try a metric wheel again, like maybe a 450 mm and maybe a 500 mm.

Capri, I remember going through “the change”. Drove us nuts at first.

But even the old sizes seem illogical. Why would not the tire in your example be an 8.3 x 15? And, if fact, a 15" wheel isn’t actually 15"…anywhere! I recently made some painting “masks” to remove and spruce up my wheels, and no dimension was 17".

I’ll also pont out that until relatively recently, cars rarely moved between continents, as you popinted out. Why would not the british done everything in metric?

And lastly, why do modern tires use a ratio for the sidewall height instead of either metric or inches? I cannot see the sense in using a ratio.

I kind of suspect that it’s like all the other industries that “code” things rather than just saying them. Come to think of it, sidewalls are filled with “codes” that nobody can read without knowing the system or having a cheat-sheet. Why shoud a load rating say “60” instead of “550lbs” or “250kg”?

Iguess my feeble neural sinapses aren’t capable of understanding the mysteries of the universe.

Max Access by Craftsman. Maybe I’ll measure it but maybe not. Magical Metrical Mystery Tour.

The tire change is NOT universal. Larger truck tires still use the old size.

My Pathfinder came with two different sizes (depending on trim level).

265/70-15 or 31x10.

1/4" = 6.5mm
3/8" = 10mm
1/2" = 13mm
9/16 = 14mm
5/8 = 16mm
13/16 = 21mm

Maybe not perfect, but close enough if that’s all you have…