Shimano Deore M6000 leaks, leaks and more leaks. Long-term review

Since 2018 I’ve spend some time on several sets of these brakes, and eventually I’ve given up on these brakes, due to several reason, more on this further down in the review.

Now it’s 13.08.2020 and I’ve updated the review to a long-term review.

As the title suggest this is a horror story, but I am not afraid of Hydraulic brakes, but I have has horrible luck with these, but I want to try four piston brakes eventually.

The brakes feel about same as Shimano M615.

The First set when they were quite new.

Make sure to apply Loctite to the threads for the reach adjustment, the lever will come out of adjustment quite fast without doing so.

Archer D1X & RevGrips

I noticed the paint on the bleed screw was wearing off after on the first ride.

Tesa Grip Tape as brake lever grip after few weeks

I installed Tesa Anti Slip Tape on all controls including the brake levers, no more slippery brake levers.

e13 Dropper post remote 17J V10SS;

I replaced the Stock Resin pads with Shimano ICE-TECH J04C metallic pads, for longevity and stopping power.


Shimano M6000 Original Resin standard pads,, Uncut 1700mm hose
Shimano M6000 finned metal pads, Uncut 1700mm hose


  • Ergonomic lever blade, they got it right. it’s better than the TRP Spyke & M930 levers.
  • I like the light lever feel, there is enough lever trow so it’s easy to control the braking with minimal fatigue, I can’t feel any friction or play in the lever.
  • You can use XTR finned pads.
  • The reach adjustment is easier to access than the previous model (M615).
  • Minimal play in the lever, there is maybe 1 mm play or less. So much less than TRP Spyke ML800 mechanical levers



  • Horrible clamp/mount, horrible bolt placement, resulting in bad clearance
Archer D1X remote

and does not work well with Archer D1X trigger, you need to mount the remote in so it fits in the gap of the clamp,so if brakes levers are flat the shifting will be compromised, horrible combo, this renders this brake useless for me.

The new M6100 brakes has a much better clamp, it has more clearance, the newer brake is also stiffer. You can check out LoveMTB video comparing these brakes.

Shimano Product page for M6000 lever:

Shimano Product page for M6000 caliper:

Shimano Product page for M6100 lever:

Shimano Product page for M6100 caliper:

Archer D1X & RevGrips
Shimano XTR SL-M9000
Tesa anti slip tape on XTR M9000 shifter
Shifter adjusted closer to fit me better, but still was not good, because this shifter just does not fit me. So I sold it.
This image has an empty alt attribute; its file name is 26609286347_3e65d091c6_o.jpg
Before I adjusted the shifter to fit me better.

The narrower clamp allows closer shifter placement, which is what I was looking for. I ran a TRP Spyke lever for months but it did not allow me the perfect shifter position, so I had to choose best brake leverage or better shifting ergonomics, but with Shimano M6000 I don’t have to choose if using Shimano XT or XTR M9000 shifter. but that’s a flaw of the shifter, cack of adjustment, but I could never get Shimano levers to work for me well, they just don’t fit me.

Trick Stuff shifter clamp & Archer D1X shifter+ TRP Spyke ML800

I now use Archer D1X Trail, much better system, it fits me much better and eliminate fatigue. but it did not fit with this brake. but with TRP Spyke ML800 it worked better, Archer D1X shifter mounted to hinged TrickStuff shifter mount next to TRP SPyke ML800 mechanical brake lever.


Here you can see the shifter remote position dialled on my new bike.

Remote position is dialled.
Remote position dialled.
  • The modulation is not the greatest, the Servo Wave means the brake actuation is progressive, so there is a deadzone at the beginning of the stroke/throw, and progressively the mechanism presses the piston more, I am not a fan of this, I prefer to have a direct actuation, with TRP Spyke mechanical levers I have direct pull ratio.
  • The brake levers body have some play, it rocks in and outwards, when I apply the brakes, I am sure the plastic I-spec placeholders contribute to this, also there is no extra support, this makes the brake. Less firm feeling, and compromises the braking performance, because if the lever is pivoting like this, the lever moves inwards,the brakes are feeling less powerful.
  • The brake lacks proper adjustment, the reach adjustment just moves the lever in or out, what this means is kids can’t use this brake, but this brake is most suitable for people between medium to large fingers.
  • The housing kinks easily, but I haven’t kinked it but it’s the same as on older brakes so not most robust hose.

  • The housing scratches very easily, after installing zip ties and removing zip ties I noticed the hose was quite scratched up.
BRake line damage_3665
  • Seems like Shimano used faulty seals, or bad seals, one rear brake lasted few months, another lasted few rides, then front brake leaked, swapped it, and installed a fresh set, and it leaked after few short rides, caliper was covered with mineral oil. and of course I overheated the rotor, glazed the pads and rotor. Also quality control is not great if this happens, to so many brakes, I doubt they test every single brake before they go into the box,each brake has to be tested, and high quality seals must be used. I don’t know which seals shimano uses on these brakes.
  • I’ve experienced issues with gravel wearing out the pads, bending the pads under hard braking. I also managed to damage a piston.
Bent Shimano J04C Metal pads _20181106_123214
Bent Shimano J04C Metal pads _20181106_123038_0Edit
Brake hose damage_3251
  • Play in the hinge causing the lever to rock back and forths the handlebar.
    The plastic cover is concerning, it’s not so exposed as other components.
  • The rear brakes i got had too little fluid, so the pads were too far from the rotor, I installed one rear brake first, and and it felt wrong, I tried another brake, and same problem but it was slightly firmer, I haven’t tried all of the brakes I got, but I will have to fill them with more fluid. This might have been due to the piston seals leaking.

March & April 2019

Shimano M6000 leak
Shimano M6000 leak

I had issues with air in the system and spongy lever feel, and inconsistent braking power, I cleaned the rotor, pads, sanded them, the brake were bled to perfection, I rode and the air bubble came back, the same feeling, the inconsistent braking power, and spongy feeling, and pads getting glazed.

I think this is due to worn seals, causing leaks contaminating the pads, letting air in.

But this was due to faulty seals I am sure, seals wear out, and need to be changed, that’s normal, but not that fast, but they don’t come with spares, and you can’t buy spares, so you have to contact Shimano to get spares I think, unless they will send you a new brake.

So after few months on those, I swapped brake to another fresh set and it leaked after few weeks, until front brake leaked, I rode and sent the leaking shimano brakes, and 40 mins later I overheated the front rotor due to a a front brake I installed, the caliper was full of fluid, the rotor got so overheated it changed color slightly, I had to sand it, and I gave up on Shimano brakes, I put the TRP Spyke back on, which eventually went on my new bike.

But I suspect the other remaining set might be leaking slightly, because I saw wet spots in the box after leavings the brakes in the original box for months. if that’s the case all replacements were leaking. and I had terrible luck.

but I can’t take this anymore, this is rediculous.

Each brake has to be tested before being shipped, so no brake sent out is leaking, or will leak in short term use, and I think brakes should ship with spare parts or be easy to get spares, without having to go with aftermarket seals from Aliexpress, but this is an option if you are out of warranty and Shimano won’t help you.

Shimano M6000 leak, I suspected a leak in caliper seals, and this one after few months leaks near the olive, hose, but my suspension was confirmed, it was leaking via piston seals at the caliper.

New bench

So I cut the hose and installed new olive, but it was still leaking.

and the calipers were leaking, I was sure at this time they were actually leaking, completely soaked in mineral oil.

BRake pads

here you can see the aftermath of leaking pistons

BRake pads

you might not notice it but the backside of the pads are completely covered in mineral oil.

Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000
Leaking Shimano M6000

Leaking brakes

Leaking brakes, caliper,pads were soaked, the piston has chipped.
pads contaminated abusing the rotor, I had to sand the rotors, install new brakes, with fresh pads and sanded rotors, it works now, but I seem to destroy shimano brakes quite fast, way too easily. I need something that fits me better, need proper reach adjustment that does not affect the actuation/power, which these do, so I had to compromise so I’ve chosen a between spot that is usable, but not perfect, I guess if I had it perfectly adjusted it would not abuse my fingers as much.

Leaking brakes

Because I was sick and feeling so bad a lot I have’t used these brakes as much as I would want to, first brake leaked, so I replaced the rear, but now both leaked, so I had to replace them. I still have working set on the Trek 6300, and one front brake that’s unused. If I get leaking I can swap to those, if it happens on those I am out of working brakes, I need to contact a dealer and try warranty.

Leaking brakes

I will have to send the brakes in for warranty, but I am tired of leaking brakes and these issues, so I might need to stick to mechanical brakes, or upgrade to a better brake, and have spare parts, so I can rebuild it.

The last pair of brakes I had on the bike leaked via the lever too

Leaking Master cylinder Shimano M6000
Leaking Master cylinder Shimano M6000

A year later I haven’t heard anything from the shop I sent the brakes to, no forwarded message from Shimano.

I will have to contact the shop and see if shimano has forgotten me, or refused to deal with me anymore, or if shop forgot me, or what else has happen. but I have had a very bad experience so far.

I’ve sent the shop I returned the brakes to a email, and I will update you on further developments.

Last video of the bike, which includes the M6000 brakes: