[Bozman52]

This is going to be a long one, but I want to share the output from the massive amount of research I've done on bolt-on brake upgrades for the F10, which culminated in my decision to do an X5M/550i hybrid on my 530d.

There's another fantastic thread that's devoted to various bolt-on brake upgrades for the F10 that was EXTREMELY helpful for me when putting together my chosen upgrade, but I wanted to create a clean thread for this specific upgrade to try and save people the trouble of spending as much time on it as I did. However, I highly recommend this thread too, as there is a lot of fantastic info in it: https://f10.5post.com/forums/showthread.php?t=1488894

My thread will be focused on converting the stock 530d braking system (or any non-M5 F10) to have E70/E71 X5M/X6M calipers/rotors in the front and F10 550i calipers/rotors in the rear. The benefit of this modification is that you get 4-piston Brembo calipers in the front with much larger rotors, and in the rear you get a slightly larger rotor, but still have a similar single-piston rear caliper as before. Theoretically, you should get better stopping power and reduced brake fade, but let's be honest, it's mostly for looks. No one is taking their 530d onto a track . . .

For rear brake options, the 550i is really the only bolt-on modification. This is because of the electronic parking brake. You can check the link above for other options, but everything else was just too involved for my liking.

Here are the specs on the brake rotor sizes across a few models for context:

- 530d: Front 348x30mm, Rear 330x20mm
- 550i: Front 374x36mm, Rear 345x24mm
- X5M/X6M: Front 395x36mm, Rear is not applicable to this application

I actually completed my brake upgrade about 1.5 years ago and have just never got around to posting, so apologies for this. However, this means that I've put quite a few miles on my upgrade and am happy to report that I've had absolutely no issues with it whatsoever!

This whole upgrade started because I needed to change the rear brake pads . . . and I ended up replacing the ENTIRE braking system . . . as one does, right? I knew my front pads would need to be replaced soon, and as my car was approaching 90k miles, I figured I should put remanufactured calipers on anyway. After an ungodly amount of research, I determined it would cost me £1,100 to replace the whole braking system with new rotors/pads and remanufactured calipers all with standard 530d equipment. If I wanted to do the same thing with X5M calipers/rotors in front and 550i calipers/rotors in the rear, it would cost me £200 more . . . so it wasn't really a choice. Note that I did all the labor myself, so my prices here are just for parts. As such, I'm in this entire mod about £1,300.

The whole conversion is completely bolt-on and no modification to your F10 is required. The only thing you will need that is not off the shelf from either BMW or an aftermarket supplier are longer front caliper bolts (4mm minimum longer) and a 4mm spacer that will fit between the front caliper and the hub to push the caliper outboard slightly. This is because the X5M rotor is 4mm outboard to that of the F10. Literally this is it, though. A few people have put M5 brakes onto a non-M5 F10, but this requires either changing to M5 hubs or getting a custom bracket made. It's doable, but a lot more work, and significantly more expensive.

I was concerned about the weight of this set up, as the X5M caliper and rotor add a significant amount more than the stock set up. In fact, a single X5M rotor weighs in at 17.25kg, which is only 0.25kg less than a 530d rotor, caliper and caliper carrier COMBINED! Here's what we're looking at:

Rear: 1.5kg more per wheel (3kg total)
Front: 7kg more per wheel (14kg total)

I was initially concerned about this added weight, especially as it's rotational and unspring weight. However, I can tell you that I've not noticed any decrease in acceleration or detrimental attributes to handling. I appreciate that going from an 11.6kg rotor to a 17.25kg rotor MUST have a negative impact on things, but as this is not a 911 GT3 that I'm tracking, I'm here to tell you that it isn't something you'll notice even in spirited backroad driving.

Anyway, here are the official BMW part numbers for everything you need for this X5M/550i upgrade:

E70 X5M Front Parts
Front Rotor (left and right): 34116789069, 34116789070
Front Caliper (left and right): 34117847241, 34117847242
Front Caliper Carrier: Not required- there is no carrier
Front Pads: 34116799964
Protection Plate (left and right): 34116775269, 34116775270


F10 550i Rear Parts
Rear Rotor: 34216775289 (same both sides)
Rear Caliper (left and right): 34216793047, 34216793048
*Rear Caliper Carrier (left and right): 34216793053, 34216793054
Rear Pads: 34216775346
Protection plate: Not required- same on all F10s

*Note that you MUST use these specific caliper carriers. If you have anything less than a 550i, you will not be able to reuse your existing caliper carriers.

The standard F10 brake pad wear sensor can be used on both front/rear calipers, but you obviously should buy a new one. Part numbers for this are: Front- 34356791958, Rear- 34356791962. I'd also recommend replacing the brake lines while you're at it: Brake hose, rear- 34326775259, Brake hose, front- 34326775261. I opted for a set of stainless steel braided brake lines, which I'll discuss in a minute.

Regarding the calipers, I found a remanufactured set of X5M/X6M calipers on ebay for £450. They also came powdercoated in whatever color I wanted. This part WILL be the deciding factor as to whether or not you do this upgrade, as the prices vary significantly for these calipers and you do not want to buy them new from BMW. If you can't find these calipers for a decent price used or remanufactured, then I'd recommend you check out the thread I mentioned at the beginning and throw on some 750i/760i calipers instead (also direct bolt on, but single piston).

For the rear calipers, I found a used set of 550i calipers on ebay and sent them to the same place I bought the X5M calipers from for sandblasting/powdercoat/rebuild.

Regarding rotors, I went with aftermarket ones made by Zimmerman. They have a cross drilled option, so I went this route. Again, there really isn't a performance advantage to this, but it does look better. Her are the Zimmerman part numbers:

Front left rotor: 150.2947.52 (BMW #34116789069)
Front right rotor: 150.2948.52 (BMW #34116789070)
Rear rotors (left and right): 150.3480.52 (BMW #34216775289)

Regarding pads, I was tired of the infamous BMW brake dust, so I went with ceramic pads instead of metallic. I appreciate that this decreases the performance of the brakes, but once again, I'm not tracking the car. It's next to impossible to find ceramic pads for the X5M calipers, and I found only one supplier: Powerstop. I went with the Z23 EVOLUTION SPORT CARBON-FIBER BRAKE PADS for both the front and rear calipers: front part# Z23-1429, rear part# Z23-1469 (https://www.powerstop.com/product/po...on-brake-pads/).

Regarding the stainless steel brake lines, this would seem straightforward, but it's a bit tricky. Basically, most SS lines don't have the same OEM fittings as the BMW lines. The BMW ones have a notch that "locks" them into place. Most aftermarket SS lines do not have this. That's not to say the aftermarket ones don't work, but I wanted a set that had the same fittings as the OEM BMW ones. I found a company called Techna-Fit that had good reviews on the forums (https://www.techna-fit.com/auto.html). I spoke with them and they confirmed the fittings were the same as BMW, so I went with these guys. My only complaint is that I think the rear line could benefit from being another 1-2" longer, as when I have my car on the jack, there is a bit of tension on the lines.

General Tips/Tricks/Considerations
- I HIGHLY recommend that you paint the rotors if you get the Zimmerman ones I used. They look to have a very durable grey coating on them from the factory, so I did not see the need to paint them. However, after a few months rust started showing through. I had to take the rotors back off, sand them down, and paint them, which was a massive pain and would have been so much easier to do upfront.

There is a company I found in the US called Brakenetic (https://www.brakenetic.com/) that sells really nice rotor/pad kits that come pre-painted. If I didn't have to pay shipping and import fees into the UK, I would have bought rotors from them. I spoke with them and they were very knowledgeable, friendly, and were willing to assist with my conversion.

- You will need to trim the protection plate on the front a bit to make room for the massive X5M caliper. I did this with just wire cutters, as it doesn't need to be pretty.

- The brake pad anti-rattle clip on the front calipers kept moving into the top of the pads and squeaking, so I just bent the tab a bit with a screwdriver to make sure it stayed in place.

- You will need to bleed the entire system when you're done, starting with the rears. I'd recommend you buy a pressure bleeder to make the job easier. Also, while you're doing the job, make sure your master cylinder doesn't drop below the minimum mark, as you don't want to introduce a massive amount of air into the system. When you remove the calipers, fluid just barely drips out, so it is very easy to manage.

- The front rotors and calipers are HUGE and I don't believe you can do this with anything smaller than 20s. Maybe 19s would work, but I cannot confirm. In my photos, there appears to be a decent amount of space between the rotor/caliper and inside of the wheel. However, with my hand in a wash mitt, I cannot get it between the rotor and wheel. For the calipers, I have to clean them with a wash cloth, as I cannot fit my bare hand between the wheel and caliper.

Also, as the caliper/rotor are 4mm outboard from the stock F10 setup, you'll notice there is very little clearance between the spokes of the wheel and the caliper. I believe you will have to have some kind of concave wheel to make this work. I have stock M5 343M 20" wheels on my car with no spacers and it fits fine, but if you have something different, then it's hard to say if this mod will work with your wheels. You could always add spacers, but then you may run into rubbing issues with the fenders.

That's about it, so if you made it this far, I hope you have found this useful. Please don't hesitate to contact me if you're interested in the mod and want more info!

[Unspec]

This is pretty expensive/heavy for what effectively is an aesthetic upgrade. Stock brakes provide more than enough braking power, and I seriously doubt 99% of F10 owners are driving their cars hard enough to run into real brake fade issues.

But hot damn do they look good.

[Bozman52]

I would completely agree that the stock brakes are fine for this car, which is why I'm not even trying to hide that I did this mostly for looks. My car lived in Scotland for most its life, so some of the braking system components were pretty rusted. The rear calipers were downright terrifying. I felt that at 90k miles, I should at least put remanufactured calipers on the car if I was doing a brake job. The rotors all needed to be replaced, so those all had to be new anyway. Once you start adding it all up, even the stock system is expensive to work on.

When I ran the figures, I was genuinely shocked that it was only £200 more to do this mod than to just put the stock system back on, so how could I not?! I'm really happy with how it turned out, especially now that I've painted the rotors. That OEM Zimmerman coating is worthless.

I guess this mod might be for those people who are looking to do an M5 brake swap, but then come across this option instead.

[ramman434]

This is great info, as I'm needing to replace my rears in the next few months. I was just going to upgrade to 550i brakes (I have a 535i w/19" wheels).

This is still great detail that I can use. Thanks for this!

[Unspec]

Originally Posted by Bozman52

I would completely agree that the stock brakes are fine for this car, which is why I'm not even trying to hide that I did this mostly for looks. My car lived in Scotland for most its life, so some of the braking system components were pretty rusted. The rear calipers were downright terrifying. I felt that at 90k miles, I should at least put remanufactured calipers on the car if I was doing a brake job. The rotors all needed to be replaced, so those all had to be new anyway. Once you start adding it all up, even the stock system is expensive to work on.

When I ran the figures, I was genuinely shocked that it was only £200 more to do this mod than to just put the stock system back on, so how could I not?! I'm really happy with how it turned out, especially now that I've painted the rotors. That OEM Zimmerman coating is worthless.

I guess this mod might be for those people who are looking to do an M5 brake swap, but then come across this option instead.

For $200 extra, makes a lot of sense. At least over here in the states, the cheapest set of X5M calipers I could find were 1.5k+

[Bozman52]

Oh my God, that's crazy money!!! I literally paid £450 for mine and they came fully rebuilt and powdercoated in whatever color I wanted.

[ezaircon4jc]

Originally Posted by Unspec

For $200 extra, makes a lot of sense. At least over here in the states, the cheapest set of X5M calipers I could find were 1.5k+

It's 200 POUNDS; about $275.

[Unspec]

Originally Posted by Bozman52

Oh my God, that's crazy money!!! I literally paid £450 for mine and they came fully rebuilt and powdercoated in whatever color I wanted.

Is this a company doing this, or just a one off ebay seller?

Originally Posted by ezaircon4jc

It's 200 POUNDS; about $275.

Whoops!

[Bozman52]

I got the front calipers from this company: https://www.facebook.com/aacoresuppliesltd/. The rears I purchased myself on ebay from an individual, then sent them to AA Core for the rebuild and powdercoating.

I've looked on ebay and it appears they are no longer offering the £450 deal I got. They had that deal up for over a year, so it wasn't a one off. They
apparently now charge £575 to recondition X5M brakes you already own (front and rear) https://www.ebay.co.uk/itm/BMW-X5-X6...gAAOSw7oBeOnZL.

They also appear to be using my brakes as the photos for their auction, which I wasn't aware of until just now. This is a bit misleading, as X5M rear brakes are not the same as 550i, as they do not have the electronic parking brake attached to the caliper. But whatever . . .

Anyway, AA Core was pretty easy to work with and is very responsive when you need something. I'm a bit on the fence about giving them a full on recommendation, as they don't have a clue how to powdercoat. It took them two tries on my rears and FOUR attempts to get the fronts right. They would always arrive with chips, runs, non-matching colors, etc. and I'd have to send them back. It was a nightmare, but AA Core was always willing to try and fix it with no questions asked, so I'll give them credit there. Even the calipers that I actually put on my car were not perfect, but I just couldn't continue the back and forth.

Therefore, I would say that if you have someone you know who can actually powdercoat calipers, you could get the calipers from AA Core, but have someone else do the powdercoating. It sounds like a pain, but it would have saved me a lot of time if I'd done it this way. They're good people, though, and that's also saying a lot these days, so I don't want to be too critical.

If you're interested in something they don't offer on ebay, just message them and ask. They didn't advertise 550i rears, but they tried to procure some for me once they knew what I was trying to do. However, you would have to pay shipping and import fees outside the UK, so that could be pretty hefty.

[n3985]

How is the brake pedal feel?

One thing I found odd on the non-M5 F10s is that despite bigger brakes from factory depending on engine i.e. 550i bigger than 535i, the master cylinder is same size across all models according to RealOEM.

[Bozman52]

Originally Posted by n3985

How is the brake pedal feel?

One thing I found odd on the non-M5 F10s is that despite bigger brakes from factory depending on engine i.e. 550i bigger than 535i, the master cylinder is same size across all models according to RealOEM.

That is correct about the master cylinders being the same across all non-M5 F10s. The pedal feel is slightly "spongier" than it was before, but I think this is due to my brake pad choice of going with ceramic. I've head this kind of response from others with the stock braking system who changed to ceramic pads. The stock system with stock pads "bites" a lot, which is something I had to get used to. I feel like my setup now is actually more comfortable for a street application, as the pedal isn't so twitchy about the amount of pressure I put on it. However, it stops in a hurry if I ask it to!

To be clear, the system feels very solid, so I feel like the master cylinder setup can support this brake system. The other guy who did this mod did not change the master cylinder and also felt it was fine, which is why I opted to leave my master cylinder as is.

[addy27]

This is awesome!! Thanks for the detailed post!!!


For the rears, you could put the M5 brackets and 550i or M5 calipers (calipers between 550i and M5 are identical) with F01/F07 rear rotors and that should fit. I believe that is what Alpina did with the B6 2016 and newer and painted them RAL5002 (Ultramarine Blue)

[Bozman52]

Originally Posted by addy27

This is awesome!! Thanks for the detailed post!!!


For the rears, you could put the M5 brackets and 550i or M5 calipers (calipers between 550i and M5 are identical) with F01/F07 rear rotors and that should fit. I believe that is what Alpina did with the B6 2016 and newer and painted them RAL5002 (Ultramarine Blue)

Hey addy27, glad to see you found my new thread, as you were really active on the other one. I know you put the 760i front calipers on your car, which look great, but did you end up doing something with your rears too?

That's interesting on the rear setup you mentioned. I didn't realize this was a possibility, as I don't recall it being mentioned on the other brake thread (although I stopped following it after a while). All the part numbers on RealOEM for rear calipers/carriers are different between the 550i and M5. The drawings of the calipers look identical, though, so do you know why the part numbers different?

The rear rotors on an M5 are massive, at 396x24mm, so I would assume the M5 calipers are designed to hold larger pads to accommodate the larger rotor surface. It looks like the F01 rear rotors are 370x24mm, compared to the 550i of 345x24mm. So now it looks like I didn't upgrade my rears sufficiently !

[Surly73]

Originally Posted by Bozman52

That is correct about the master cylinders being the same across all non-M5 F10s. The pedal feel is slightly "spongier" than it was before, but I think this is due to my brake pad choice of going with ceramic.

A few comments for this thread off the top of my head.

My question was also about brake feel. I generally don't feel that my 535 needs more brake torque, but I have always felt that every non-M 5 series needs better brake feel. The best BMW brakes I've owned were on my E90 and they were tiny compared to my F10 and were single piston floating caliper design. While not as good as 4 piston fixed caliper Porsche brakes I've also owned in the past, they had great bite, very hard pedal, and were extremely confidence-inspiring even with stock pads.

Every non-M 5 series I've driven from E34 to F10 has soft, uninspiring brakes no matter how massive the parts are at the wheels. This goes in line with every other control (signal stalks, shifters, window switches) - soft and slow. This is clearly a design decision that is not going to be trivial to undo.

The F10 M5 I've driven although braking was still not as nice when driving spirited firmed up far nicer and inspired more confidence when you started getting hard on the brakes. I think part of that is compound, which brings me to...

F10 factory compound is ceramic from everything I've been able to figure out. For F-series non-M BMWs it appears that BMW has moved to ceramic as factory/dealer pads and they have less bite and way less dust. This same M5 I drove dusted like crazy with dealer pads so they were "old OE" compound. On my last brake job I was SEEKING OUT dusty, grabby "old OE" pads. It seemed nearly impossible to determine without a doubt what you were getting at the time you ordered - no one seemed to know at ECS/FCP/Rockauto etc...

It does appear that the Pagid pads I ended up getting for the front were, in fact, dusty "old OE" like I wanted and they do bite better. I'm hoping the Textars I have on the shelf for the rears also go that way.

[Bozman52]

Originally Posted by Surly73

F10 factory compound is ceramic from everything I've been able to figure out. For F-series non-M BMWs it appears that BMW has moved to ceramic as factory/dealer pads and they have less bite and way less dust.

This doesn't match up with the research I've done historically, as F10s definitely came from the factory with metallic pads as far as I'm aware. If you take the part number from RealOEM and order those pads from BMW, you should get metallic pads.

That being said, it would not surprise me if some dealers have made the decision to swap out the OEM metallic pads for ceramics when they perform pad replacement on customer cars. The brake dust of BMW OEMs is horrendous and almost every brake pad thread on here will see a lot of complaints about it. I have no doubt the standard dealership customer complains endlessly about it.

From my experience, if you want ceramic pads for the stock braking system on an F10, you have to specifically seek them out. If you just do a parts search for the brake pad number on somewhere like https://www.buycarparts.co.uk, most of the aftermarket OEM replacement pads that come up are going to be metallic. There are a handful of ceramic options, but far fewer than the metallic counterparts.

[addy27]

Originally Posted by Bozman52

Hey addy27, glad to see you found my new thread, as you were really active on the other one. I know you put the 760i front calipers on your car, which look great, but did you end up doing something with your rears too?

That's interesting on the rear setup you mentioned. I didn't realize this was a possibility, as I don't recall it being mentioned on the other brake thread (although I stopped following it after a while). All the part numbers on RealOEM for rear calipers/carriers are different between the 550i and M5. The drawings of the calipers look identical, though, so do you know why the part numbers different?

The rear rotors on an M5 are massive, at 396x24mm, so I would assume the M5 calipers are designed to hold larger pads to accommodate the larger rotor surface. It looks like the F01 rear rotors are 370x24mm, compared to the 550i of 345x24mm. So now it looks like I didn't upgrade my rears sufficiently !

Essentially, for fronts, Alpina edition 50 went with the X5m calipers as can be seen here. Im sure they either also used a washer..as I doubt for such a limited version they would have modified the hub or asked Brembo for modified calipers. SO im sure in some secret Alpina parts catalog there is an actual part number for the 4mm washer

:https://f10.5post.com/forums/showpos...&postcount=146

And for rears im 99.99% sure they went with M5/M6 carrier with 550i caliper and the 370x24 rotor from F01/F07 v8s. I test fitted this rear setup on my car, just haven't switched yet because I had plenty of pad left on the current setup :

https://f10.5post.com/forums/showpos...&postcount=177

REAR CALIPER ONLY for 550i/M5/Alpina: part numbers for the calipers (rear only for this conversation) are different because M5 calipers come painted (blue or gold) where as Alpina B6 2016 and newer come painted RAL5002. On the 650i (F06 and F12/F13) you could get black painted calipers for all 4 corners and they have a different part number too even though they are identical in dimensions to regular 650i non painted/gray calipers.

CARRIER : For M5 to accommodate the bigger rotors, the caliper carrier bracket has a slightly extended leg where it mounts to the Hub. I just took a chance and bought M5 rear brake caliper and carrier set thinking Alpina had to have dug into the BMW parts bin for their brakes. Also, from realm, you can see they used the 370x24 rotor started 2016, so I tried to also mix and match this combo and they bolted right up. Makes sense though as both companies share a ton of engineering info so they are able to pick and choose parts.

This photo is closest I can find that shows Alpina Edition 50 rear brakes..

https://www.alamy.com/stock-photo-fr...137826333.html

Lastly, if massive stock brakes is the goal, the biggest offering by BMW was the one on the 760i security version (and on the Rolls Royce).. The front rotors on that beast are 410x36!! However, they do come with a hub part number that is specified for that car only so dont know if they would be bolt on for us mare mortals.

https://www.realoem.com/bmw/enUS/sho...diagId=34_1753
https://www.realoem.com/bmw/enUS/sho...diagId=34_1823

[Surly73]

Originally Posted by Bozman52

This doesn't match up with the research I've done historically, as F10s definitely came from the factory with metallic pads as far as I'm aware. If you take the part number from RealOEM and order those pads from BMW, you should get metallic pads.

That being said, it would not surprise me if some dealers have made the decision to swap out the OEM metallic pads for ceramics when they perform pad replacement on customer cars. The brake dust of BMW OEMs is horrendous and almost every brake pad thread on here will see a lot of complaints about it. I have no doubt the standard dealership customer complains endlessly about it.

From my experience, if you want ceramic pads for the stock braking system on an F10, you have to specifically seek them out. If you just do a parts search for the brake pad number on somewhere like https://www.buycarparts.co.uk, most of the aftermarket OEM replacement pads that come up are going to be metallic. There are a handful of ceramic options, but far fewer than the metallic counterparts.

There could be a regional component to this too.

My F10 was brand new "in the family" (I wasn't driving it at first). Compared to every other German car I've owned and serviced (including friends and family) I was astonished at how low dust it was. During the factory maintenance plan rear brakes were required. The new set from the dealer was also virtually dust free.

I did my own front brake job 13 months ago using Pagid pads and rotors (as described, I was trying to find original OE compound) and now they're super dusty like I'm used to. The rears are still dust free.

In all my research when preparing for the front brake job, I found indications that F series cars are ceramics from the factory.

[addy27]

Never thought I'd be happy hearing brake squeal, but finally, im getting some from the rears... the time is ripe to install the M5 setup and post more pics/info.. hopefully before March!

[Flying_Squad]

Bozman52, great work, I admire what you've done here

If going down the single piston route and getting the biggest possible upgrade from this option, does anybody know if it's possible to utilise front calipers from an F12/F13 F06, in combination with 374x36mm discs, in case it's not possible to source F01 750/760i front calipers?

[addy27]

Depends on what model F12/F13/F06 you're starting with but the second post on this thread should answer your question :

https://f10.5post.com/forums/showthread.php?t=1488894

[OppositeLock72]

This is awesome information, thanks Bozman52! Its so helpful to the rest of us when someone takes the time.
Track days in my 550i are hamstrung by my open diff and my brakes! And here i thought when I bought the car the brakes were huge - they're still too small! I guess these cars are no Caterham.
I haven't heard anyone mention brake balance yet - changing the caliper diameter ratio and changing rotor diameter ratio can do wonky things with the brake bias - anyone have comments on this?

[Unspec]

Originally Posted by OppositeLock72

This is awesome information, thanks Bozman52! Its so helpful to the rest of us when someone takes the time.
Track days in my 550i are hamstrung by my open diff and my brakes! And here i thought when I bought the car the brakes were huge - they're still too small! I guess these cars are no Caterham.
I haven't heard anyone mention brake balance yet - changing the caliper diameter ratio and changing rotor diameter ratio can do wonky things with the brake bias - anyone have comments on this?

Realistically, these cars are just too heavy for serious track use.