All the brake dust is on the front as "normal"?
Doesn't sound normal to be. Every car I've ever owned has had brake dust on all four wheels. Some, like my Volvo, have more on the front but it's not hard to see the brake dust on the rear wheels!
Lube those caliper bolt pins!
- Thread starter Lbear
- Start date
All the brake dust is on the front as "normal"?
Doesn't sound normal to be. Every car I've ever owned has had brake dust on all four wheels. Some, like my Volvo, have more on the front but it's not hard to see the brake dust on the rear wheels!
On mine most of the brake dust is on the front wheels with a very light dusting on the rears. To be honest my CX5 has the worst accumulation of brake dust on the front wheels of any car I've owned, they can be black within a week.
Cheers all
Jonno21
Cheers all
Jonno21
- :
- Plano, Texas, USA
I believe you're correct. Mazda Service Manual (Thanks to Chris_Top_Her) says use "rubber grease" on these pins and "anti-rattle brake grease" on back of brake pads, shims, and the guide. Honda Service Manual says use "silicone grease" for caliper pins、piston seal; ”rubber grease” for piston boot; and ”Molykote” moly grease (anti-rattle brake grease), which is included with OEM brake pads, on back of brake pads, shims.
Last edited:
If I get some time on Sunday I might inspect and lube my caliper pins. I need to rotate the tires within 1K miles anyway so good time to do it.
- :
- Plano, Texas, USA
Yeah, I'd never done any "preventive maintenance" on those brake pins for all the cars I've owned other than at time replacing brake pads. I haven't touched rear drum brakes since new on our 173,408-mile Honda CR-V! But you may be disappointed if you don't check those pins and lub them with silicon grease as many people have found out they're definitely lack of lubrication from factory!
New Rear Brakes at 10,000?
Rear brakes gone at 15k..
When I painted my front calipers I removed the pins to separate the caliper from the bracket. I was astonished to see very little grease in the holes and on the calipers pins themselves(less than 1000 miles). I've inspected brakes on new cars before (pre 2010) and remember seeing more grease from other manufacturers. Is Mazda being stingy with their lube?? Do they have a bad brake system factory worker?! I'd suggest lubing all metal-to-metal contacts with Sylglide on all these brake systems and making sure the braking system has no unwanted stiction. That being said, newer cars these days DO have more rear brake bias than older cars due to TCS/ABS control systems. But 15,000 is way too premature to be considered normal.
Also, notice in this picture, Mazda made the pads wider than the brake rotor surface, which is becoming a trend with new cars. I believe it's engineered to "clean" rusty lips on the outside edges, which may help with NHV and appearance.
- :
- Plano, Texas, USA
This one contains moly and seems more suitable for anti-rattle brake grease. I'd try this Sil-Glyde Silicone Lubricating Compound for those pins recommended by Skorpio:If I get some time on Sunday I might inspect and lube my caliper pins. I need to rotate the tires within 1K miles anyway so good time to do it.
I only recommend synthetic lube specifically made for high temperature brake usage. I have used Sil-Glyde for many years without fail. If you go to an auto store, they should have it, or similar on their counter.
I see a lot of hits on people successfully using it and it mentions for brake sliding surfaces as well.
http://crcindustries.com/auto/?s=05351
I already have a tube of it so will let you know if it appears to not do the job.
http://crcindustries.com/auto/?s=05351
I already have a tube of it so will let you know if it appears to not do the job.
C
CX5_Pete
Use both. Put one on the right, the other on the left, compare 5,000 miles later! 
Silicone on the pins is the correct compound because while plain silicon grease is not the best lubricant, it is the best at keeping out water, thats why its recommended. There are some silicon brake greases that have moly added to assist. I put silver anti sieze on the clips and between the piston and the anti rattle plate behind the pad, tiny amount. And there is an adhesive, basically its high temp rtv that goes between the pad and the anti rattle plate, again, paper thin application. But guess what? If you load up the pins with grease it will work fine. What eva ya use, reload every time you put on new pads, and if your too lazy to reload ... then for christs sakes move the caliper back and forth and listen for the "big mixing spoon in the potato salad" sound. Those pins need to be swimming in grease to keep everything happy.
- :
- 2022 2.5GT
I worked in the brake development industry for 17 years and I cant imagine where youve been given this impression. In the US, there are regulations laid out in FMVSS and DOT approvals for braking. There are similar regulations in Europe. These call for vehicles to meet adhesion utilisation regulations which take into account the transfer of weight during a stop. All vehicles do this - it is the law of physics. When the brakes are applied when the vehicle is in motion, weight is transferred towards the front of the car as any loose item will confirm. When this happens, the weight obviously reduces on the rear wheels and there is a chance of them locking prematurely. How much weight is transferred depends on the speed of the car and how much the axles weigh but typically this might be anywhere from 60:40 to 80:20 depending on how hard the brakes are applied. For this reason the front brakes always have a bigger area of pad material to balance the wear with the rear (friction is independent of area and a small strip of friction material can hypothetically stop the vehicle in the same way a large area would, it would just wear quicker). There is usually some sort of pressure reducing valve in the rear brake line as those who have bled brakes will know - the pedal is much harder to press. This notion that newer cars brake heavily on the rear is completely untrue. If they did, they would be completely unstable, especially in the wet.
It is mike. The fronts do take on more work in normal driving and do generate more dust.
Finally, in response to some of the above comments. When a new brake is assembled in production, no grease is used anywhere except for the enclosed guide pins and then, any more than a very small amount is not more efficient than having it dripping out of the boot. Now Im not suggesting that grease shouldnt be used but if at each pad change, all the shims and the abutment clips (these little stainless clips at the ends of the pads) were renewed, in theory you should be back to new. Brake noise is a complex subject. It works in a similar way to running a damp finger round a wine glass. When the friction is just right, the glass will ring - so does a cast iron rotor. The shims have been designed to dampen that out and the clips eventually lose their spring loading. Of course some friction material has a natural frequency that is difficult to dampen and with the weight of all the components, right back to how they are attached through the suspension, make them more prone to noise that others. For that reason, the use of brake grease is often referred to by vehicle manufacturers as a service fix to compensate for the wear in these items and the greater chance of vibration. The ones to avoid are copper and aluminium based products that have a very high melting point - if you only have these on the shelf for brakes, bin them. For the back of the pad, a small smear of these proper grease like products shown above are acceptable on the back of the pad and the ears or abutments. For the guide pins, they often appear stuck when servicing brakes but if they are twisted and then worked in and out, they quickly become free and that is sufficient as long as the boot is intact. However, if a need is felt to intervene, then a small amount of rubber grease (or the proper pin grease which comes in a tiny thumb nail sized sachet in a kit) would be more than enough or some of the more modern greases like Ceratec are suitable for the pad and will not harm rubber. If too much grease is used then the pin will hydraulic and try to initially resist compression and any excess will be forced out through the boot. That often ends up with the boot getting displaced or split, water gets in and before you know it the caliper is scrap. The manufacturers do not skimp - less is more on guide pins. That is also not down to Mazda, they do not make calipers. It also worth noting that all of these greases have a melting point somewhere down near 250-300C - 480-570 F which is much lower than the pads which can get up to 1800 F at the interface with the disc. For that reason, a normal bearing grease is often far more effective than these coper and ally' greases. Let me assure you that in the braking world, performance is not a problem but these issues commonly referred to as refinement or NVH (noise, vibration, harshness) consume millions in development costs.
- :
- Plano, Texas, USA
No, I'm not against using CRC's. Just saw those service manuals always specify different type of grease for pins. I don't have any extra brake grease as Honda pads have always supplied moly grease. But even with moly/anti-rattle grease, whether it's suitable or not for pins and rubbers, is still better than lack of lubricant. Let us know what do you find if you have a chance.
- :
- Plano, Texas, USA
Use both. Put one on the right, the other on the left, compare 5,000 miles later!
But for brake pins, there's no left and right, but upper and lower pins.
C
CX5_Pete
I meant use one for the right calipers and another for the left.
- :
- Plano, Texas, USA
OK, sorry for the misunderstanding...I meant use one for the right calipers and another for the left.
Anybody who has ridden a motorcycle, street or dirt, eyebrows raised when they read that the "rears do most of the braking" .... well, lets just put it this way, the rear tires would wear faster and break traction making the ABS system go active way too much, no way rear tires brake more then the fronts, calling BS on that one, sorry. (dang it, now I am in for a good torchin!!)
C
CX5_Pete
I agree that the fronts do most of the braking. However, to reduce nose dive, it does help to apply the rear brakes first and then transition over to the front. I do that while riding my motorcycle. I learned that trick from one of the riding books I read, I forget if it was from Keith Code or Lee Parks. So in theory, if Mazda designed our brakes to do that, under casual deceleration and in stop and go traffic, I could see how the rears are wearing out faster than the front.
- :
- 2022 2.5GT
They didn’t. Measure the temps after very light braking. Mind your fingers!
The proper way to measure brake temperature is with a non-contact IR thermometer like all racing teams use. I have a professional quality one that was about $380 6 years ago. When I first heard the CX-5 used brake force distribution to transfer more of the braking force to the rear under light acceleration I tested it out. First I checked that both disks were the same temperature (ambient) and then I drove about a mile making sure to only use light brake applications. This was a couple of years ago and I don't remember the specific temperature differential, but the rears were indeed considerably warmer.
When conducting this test, it's important to be on clean dry pavement because the CX-5 can detect the presence of rain slickened pavement and will automatically send more braking force to the front. The BFD also applied more force to the rear at the initial brake initiation because weight hasn't transferred to the front yet. This initial stronger pulse to the rear helps settle the chassis (lowers the front ride height slightly and momentarily in a gentle manner) and this reduces some of the negative effects of brake dive when the front brakes are applied more strongly. Said another way, it pre-loads the front suspension slightly to reduce the momentum of brake dive.
Yes Anchorman, the BFD really does distribute more braking to the rear wheels when it's advantageous to do so. I've measured it. Mazda says it does it. You, inexplicably deny it. (spin)
