What does "M12" Signify in Part Names for Model X and Model S Brakes?

[tps5352]

The Tesla Parts Catalog (for the US) naturally lists brake parts for Model X (2015-2021), with several parts shared with Model S (2012-2016 and 2016-2021). The Performance models of both Models S and X received red-painted calipers; non-performance models received gray calipers.) For example, here are some shared part names and part numbers for Models X and X from this "Classic" period (to simplify I've omitted rear Brembo brakes, which were on the Models S/X along with separate rear parking brake calipers until ~2016/17):

Model- Years​	Part Names​	Current Part Numbers​
Front (Brembo) Brakes
Model S - 2012-2016 Model S - 2016-2021 Model X - 2015-2021​	FRONT BRAKE CALIPER WITHOUT PADS - LEFT FRONT BRAKE CALIPER WITHOUT PADS - RED PERFORMANCE - LEFT FRONT BRAKE CALIPER WITHOUT PADS - RIGHT FRONT BRAKE CALIPER WITHOUT PADS - RED PERFORMANCE - RIGHT​	1007794-00-C 1007794-01-D 1007795-00-C 1007795-01-D​
Rear (Mando) Brakes
​	​
Model S - 2016-2021 Model X - 2015-2021​	REAR BRAKE CALIPER WITHOUT PAD KIT - LEFT HAND - MANDO SERVICE KIT - FULL CALIPER ASSEMBLY WITHOUT PADS. LEFT HAND - RED REAR BRAKE CALIPER WITHOUT PAD KIT - RH - MANDO SERVICE KIT - FULL CALIPER ASSEMBLY WITHOUT PADS. RH - RED​	1097414-00-A 1097414-01-A 1097415-00-A 1097415-01-A​

So far, so good.

However, at Tesla and at certain online sites selling new and used Tesla brakes, some otherwise attractive brake products are designated with "M12" in the name/description. When asked, so far sellers have not been able/willing to satisfactorily explain what "M12" signifies, and if it is universal (to all Tesla Models S & X brakes of this period) or specific (to only certain Tesla brake versions or geographic areas, like the European market for example). No one so far can or will tell me if this an important factor for ensuring compatibility?

Having sometimes seen (arguably devious) sellers remain "silent" to North American customers about European Type 2 charging adapters and Model X European tow-ball hitch adapters, I now tend to be suspicious.

Anyway, is "M12" a Tesla thing, or does it emanate from the manufacturer: Brembo. I have so far not seen "M12" used to describe Mando brakes in the Tesla Parts Catalog. But "M12" is used in some front and rear Brembo brake Tesla part names. In the following examples (emphasis added), I have separated the Model-Years that share "M12" caliper parts and used colored arrows to indicate shared caliper part numbers:

My car does not have Brembo rear brakes, so I don't have to concern myself with the "M12" issue in the rear. But what about in the front?

1. Does "M12" refer to the caliper-bolt thread size? (E.g., a metric 12 thread size?)
   |
   • Model S 2012-2016, Model S 2016-2021, and Model X 2015-2021 seem to use the same M12 bolts for front and rear Brembo brakes (emphasis||added):
     • Part Name: BOLT HF M12x1.75x45 8.8-ZnFl
     • Part Number: 2007068-00-B
       |
   • And they use a different M12 bolt for rear Mando brakes, if they happen to use those (emphasis||added):
     • Part Name: BOLT,TE,M12X45,STL[109],ZNFL[BLCK]
     • Part Number: 1088968-00-B
       |
2. Or does "M12" refer to something entirely different (like the brake line connector size, or something else)?
   |
3. If it is about the bolt thread size, and all Tesla (Classic Models S & X) brakes use M12 size bolts, why do only certain calipers show "M12" in the part name?

I hope that "M12" is universal and not an important compatibility factor. It would make things simpler.

Thanks for any assistance you can offer. If anyone can recommend brake experts in the Sacramento, California area, please let me know. (Feel free to PM me to discuss.)

 

[tps5352]

Update:

Thinking that "M12" might be a metric size/thread designation I thought to look at European Tesla Parts Catalogs.

Apparently, Tesla does not encourage USA customers from accessing Parts Catalogs for other countries. But, using a VPN set to the host country worked for Germany, (But not entirely for the United Kingdom. I was able to access the UK Parts Catalog but at some point started having problems. No problem with the German Parts Catalog, however.)

I was definitely in the Germany Parts Catalog, because some of the words were in German. What I found surprised me. All the Models S (2012-2021) and Model X (2015-2021) brake part names and number were exactly the same as those for the Unites States. Identical.

So, no answer about "M12" there. For Models S and X (2012-2021) Germany has the same "M12" brake caliper part names and numbers, the same non-M12 part names and numbers, and the same M12 bolts for Brembo and Mando brakes.

The mystery continues.

PS -- I just registered online as a customer with Brembo, and I sent an email to Brembo asking questions about "M12" Tesla brake calipers. We'll see if I get any kind of helpful reply.

PPS -- I also sent a similar inquiry to Mando about their rear brakes.

 

[tps5352]

Update # 2:

After writing to Brembo (and receiving no reply), I called their customer service number today. Unfortunately, while polite the representative (probably located in the Indian sub-continent?) was unable to satisfactorily answer my questions. While on the phone with me he simply used Google to see that "M12" was used in certain Tesla brake part names--THAT I already knew. He also said that Brembo only listed replacement rear brakes for Model S. Not very helpful. I had to tell him that from 2012-2021 Tesla offered front Brembo brakes which were the same on both Model S and (starting in 2015) Model X. Clearly not highly trained and/or experienced. (Typical company cost-savings move--hire under-paid off-shore contractors to handle customer service.)

*****​

Regardless, I am beginning to get the feeling that "M12" may not be a critical specification. It may be something that is true for all the Tesla-Brembo brakes; so not a distinguishing factor. The jury is still out.

But then it doesn't explain why there are multiple Brembo brake calipers listed for Models S/X and some have "M12" in the name and most do not. Worrisome (when lots of money is involved).

As I told one person recently, I don't want to order a used or new brake caliper, have it painted/coated, then find out that because of "M12" it doesn't fit my car. A painted/coated caliper can't be returned, right?

 

[ngng]

M12x1.75x45

Metric, 12mm diameter bolt, 1.75 pitch, 45mm length

 

[tps5352]

M12x1.75x45

Metric, 12mm diameter bolt, 1.75 pitch, 45mm length

Yes, I noticed that in the Tesla Parts Catalog for Models S and X brakes. The same or similar parts (2007068-00-B; 1088968-00-B) are listed as the caliper attachment bolts (2 needed for each caliper) for Brembo and Mando calipers used in Models S and X from 2012 to 2021.

So if all the Models S & X use M12 caliper colts, why do only certain brake calipers have "M12" in the title?7

I've also learned that various cars can use different brake line connector sizes, sometime M10 and sometimes M12.

So I remain unclear on what "M12" really means and does it in any way affect compatibility of brake calipers with different Model X cars.

 

[ngng]

My guess is that it's just a data entry thing. M12 is not ambiguous, it means M12. How it relates to the brakes, who knows? Probably the size of the expected retaining hardware.

 

[tps5352]

My guess is that it's just a data entry thing...

Possibly.

For a state-of-the-art high-tech company, Tesla came (was forced?) into the whole online parts list thing kind of late. I suspect that they didn't invest enough resources into it. (Just some harried, low-pay staff who wish they were doing something else. They need partial-OCD people, like me, or true large-database experts who would want all the names to be consistent, all the data to be precise and accurate, and lots of interactive links from one part to another, from current parts to expired parts, from one section of the online catalog to another, and so forth.)

The other woefully-lacking aspect is the human element. In an effort to save money, Tesla (and these days most corporations) hire young, inexperience staff. They are (mostly) polite and well meaning, but I don't like it when I am clearly more knowledgeable than Tesla personal about parts. I know that I am ignorant of lots of stuff, so what is it they don't know?

And the issue of keeping customers in the dark, and limiting communications to that ridiculously inconvenient App Service messaging should definitely be changed. Buying parts should be separate from service. Two different things.

 

[ngng]

Possibly.

For a state-of-the-art high-tech company, Tesla came (was forced?) into the whole online parts list thing kind of late. I suspect that they didn't invest enough resources into it. (Just some harried, low-pay staff who wish they were doing something else. They need partial-OCD people, like me, or true large-database experts who would want all the names to be consistent, all the data to be precise and accurate, and lots of interactive links from one part to another, from current parts to expired parts, from one section of the online catalog to another, and so forth.)

The other woefully-lacking aspect is the human element. In an effort to save money, Tesla (and these days most corporations) hire young, inexperience staff. They are (mostly) polite and well meaning, but I don't like it when I am clearly more knowledgeable than Tesla personal about parts. I know that I am ignorant of lots of stuff, so what is it they don't know?

And the issue of keeping customers in the dark, and limiting communications to that ridiculously inconvenient App Service messaging should definitely be changed. Buying parts should be separate from service. Two different things.

Sorry, but I think you're reaching a bit, other OEM parts catalogs are similar.

I don't disagree about their service though.