MPG Display

[Seatman]

Can't wait 'til the US and UK decide to embrace metric.

If they could at least agree on the size of a gallon whether it's imperial or metric! Lol

 

[J_dude]

With that said, now that I think about it though, the next super-common size up is 16mm - which is the same as ⅝". So maybe....

Might just depend what you're working on, but I think I see a lot more 15mm than 16mm.

 

[Nuje]

but I think I see a lot more 15mm than 16mm.

Just going off the top of my head...
16mm: Engine/transmission mounts, rear upper and lower shock mounts, sway bar end links, heat shield over inner CV boot, most of the transmission-to-engine bolts...
15mm: Counterhold rear brake caliper bolt(?). Honestly can't think of anything beyond that off the top of my head, but I know I have used it; but seriously - I could lose the socket and have to get by strictly with a 15mm box/open end wrench and it wouldn't have a meaningful impact on any job I commonly do on the cars.

13mm by far the most common of the stuff I commonly work on, as attested to by the fact that I've lost three 13mm sockets out of various sets (and none of anything else).

 

[Zak99b5]

Don't forget the super-common 10mm, a nice round figure in metric and 'Murican--3/8". Plus that's the socket that's always walking off.....

I see more 15mm on my Ford and old Chevy than my VW.

 

[J_dude]

Just going off the top of my head...
16mm: Engine/transmission mounts, rear upper and lower shock mounts, sway bar end links, heat shield over inner CV boot, most of the transmission-to-engine bolts...
15mm: Counterhold rear brake caliper bolt(?). Honestly can't think of anything beyond that off the top of my head, but I know I have used it; but seriously - I could lose the socket and have to get by strictly with a 15mm box/open end wrench and it wouldn't have a meaningful impact on any job I commonly do on the cars.

13mm by far the most common of the stuff I commonly work on, as attested to by the fact that I've lost three 13mm sockets out of various sets (and none of anything else).

Ah you're right, there is a lot more 16mm on the VW, I was lumping all my vehicles together in a group and like Zak said, lots more 15mm on my North American stuff.

I see more 15mm on my Ford and old Chevy than my VW.

 

[dlhovland]

I always assumed that it was just that it's the "right size", not about appealing to a common imperial measure. 12mm was too small; 14mm too large - 13mm is the Goldilocks size.
With that said, now that I think about it though, the next super-common size up is 16mm - which is the same as ⅝". So maybe....

But then that theory falls apart because the next common size up from that (apart from lugs) is 18mm (not 19mm = ¾").

24 = 15/16

 

[BobnOH]

OT
My observation over the years gradually driving all domestic to all import vehicles is the imports use less sizes. Also seem be slightly smaller fasteners.
The US attempted to go metric recently in the early 70s, again in the 90s. In today's world it only makes sense to use a single standard system. Someday.................... maybe

 

[turbodieseldyke]

It's the 18mm that breaks my balls. What a stupid size. Just make them 19mm, so we can use the 3/4 from our SAE set if we cant find our 19.

 

[Seatman]

Don't forget the super-common 10mm, a nice round figure in metric and 'Murican--3/8". Plus that's the socket that's always walking off.....

I see more 15mm on my Ford and old Chevy than my VW.

3/8ths is more like 9.5mm, won't fit a 10 until it's rusty then the 3/8ths becomes a hero lol

 

[Nuje]

Yeah - that's my experience with ⅜" as well - more like 3.5/8ths = 10mm (but 7/16th still isn't a great fit either).

 

[Seatman]

Yeah - that's my experience with ⅜" as well - more like 3.5/8ths = 10mm (but 7/16th still isn't a great fit either).

That's the one for rusty 12mm bolts on Jap cars lol

 

[wonneber]

I always assumed that it was just that it's the "right size", not about appealing to a common imperial measure. 12mm was too small; 14mm too large - 13mm is the Goldilocks size.
With that said, now that I think about it though, the next super-common size up is 16mm - which is the same as ⅝". So maybe....

But then that theory falls apart because the next common size up from that (apart from lugs) is 18mm (not 19mm = ¾").

OK, here are the numbers;
13 mm is 0.51181102 inches
I have used larger American sizes on metric nuts & bolts before I had the proper metric sizes.