I have 2014 xkr conv. and have been wearing my rear brakes twice as fast as the fronts. First rear pads were changed at 17k miles. Now at 30k and they are getting close again. Fronts have not been changed yet. Every person I spoke to at 3 different dealers said it is normal for them to wear the rears first. I was told that apparently there is an anti dive system which keeps the car level when braking and that all Xk/XKRs since 1996 wear the rear brakes first. So please chime in with your experience so I can get to the bottom of this. Do your rear brake pads wear faster than your fronts?

 

Prior to the switch to ceramic pads I'd return from a spirited drive in the mountains and the rear wheels were darn near black with brake dust. Much more than the fronts. Depending on driving style I believe your assessment is correct. The rear pads are tiny compared to the fronts and they do quite a bit of work.

 

My 07 XK, at the time driven by a 70 year old women, needed rears at 20K miles. At 36K, I've got 1-2mm left before replacement and the rotors look pretty tired. Obviously, the brake balancing puts more wear on the rears and they are probably undersized for the task. My fronts lasted 32K.

 

I don't know, mine seem to wear maybe a bit more on the front. Also, my front wheels are ALWAYS much dirtier than the rears. I should have switched to ceramic pads long ago, just haven't for some reason.

 

Different people go through brakes much differently. Front brakes will AWLAYS have far more brake dust than the fronts due to them having over 80% of the stopping power/work to do and also being much larger pads so more surface friction. On my Honda I changed out the front pads at 120K miles and still have the original rears in at 160K. I've known a few ladies that would go through pads, sometimes rotors too at under 20K consistently, depends on driving technique - they don't pay for their repairs so why should they care it seems. As far as XK's go the jury is still out as to whether the rears engage more than they should compared to the fronts. FlyC2C was kind enough to provide a comprehensive step-by-step tutorial for us DIY'ers

 

Yes, the rears on the XK do wear faster than the front pads and for this reason the rear wheels accumulate more brake dust too. The faster wear on the rear is indeed because of the electronic controls that intervene. Perfectly normal for these cars - but the rate of wear is directly related to your/our driving style: more aggressive driving, more brake wear.

 

Though aggressive driving would cause more brake wear, is there any driving style that would cause the fronts to wear faster instead?

 

Driving like Miss Daisy I suppose. The stability control utilizes the rear brakes as well. Which is why in more spirited driving the rears have more dust than the fronts. Of course the 2010+ models have the e-diff but I assume the ABS is still in play. That and the "anti-dive" program that applies the rear brakes milliseconds before the fronts especially on fast brake pedal travel (or panic stop) to prevent nose dive.

 

Ok, here is a question: when the stability control comes into play and applies the rear brakes, do the brake lights flash in that impressive way that I have seen on Top Gear as those fools try to destroy the differentials (the amount of tire smoke apparently being their only criterion for the quality of any particular car).
The question is a serious one.

 

There's several stability systems that use the brakes:

DSC (Dynamic Stability Control) uses brakes and powertrain torque control to reduce understeer & oversteer
ETC (Electronic Traction Control) reduces torque and uses braking to stop wheelspin on one or both rear wheels
Understeer control reduces engine torque and brakes individual wheels to keep the car turning (not sure how this really differs from DSC, but it's listed separately)

I can't see any mention in the manual of an anti-dive element to brake application, but it may exist.

 

Those flashes aren't what you think, they come from filming LED lights. LEDs have a frequency on/off, very high rate, I don't want to look it up. Anyway, video is captured at 30 FPS, and some frames have the lights off. Sort of watching wheels on TV turn, they sometimes look like they go backwards. Same idea.

 

Nope.

 

Agreed, though I've seen in person (i.e. not on video) the brake lights on a 2013 Vauxhall Insignia flash under heavy braking - must be a feature of their higher-end models. Quite impressive.

 

I bought a Flasher unit from some LED store through eBay and hooked it up to my Spoiler Brake light only. I have it set on ten flashes per second, three seconds then on solid.
Here in the US the Department of Transportation has not allowed the Flash-Per-Hard-Braking for any cars manufactured. They say it would be "Distracting" and cause more accidents.

 

Thanks for this explanation, which makes perfect sense. The behaviour of the Top Gear crew does not; abusing cars is for adolescents. Ah well, they are gone now. But they were funny, I admit.

 

NHTSA allows 4 flashes under FMVSS. Mine does 5, but no one
has ever said anything.

Tailgaters *really* don't like them at night, they go around or
fall back.

I'm happy, they're happy

 

Flashers: I use the Kahtec Smart stop delay. Easiest $25 investment you can make to your car.
Brake dust: Interesting that I have never noted the pad wear front to rear.
I spent solid money on the front and rear rotor and pads (StopTech Cryo/slotted rotors paired to EBC Yellow Stuff pads) on my base '07 XK.
(Alas she has now been replaced with a 2010 XKR.)
I foresee Slotted and Cryo rotors in my 2010s future as well, but I also need to start digging into some serious pads soon (Ceramics are NOT a serious pad). But, that is only after I get off these garbage OEM Dunlops and back to something sticky for tires!

BTW: EBC Yellow Stuff did well for my base XK, as I pushed them hard with only minor fade. However regardless if advertising, they still require warming up before they bite hard.
V

 

I beg to differ. While I havent invested in a flasher unit, I've gotten into the habit of turning on my hazards briefly when traffic slows down considerably in front of me or stops. I've noticed when I do that, the car behind me brakes a lot sooner and backs off my tail. As far as the brakes, it appears to me that my fronts wear out twice as fast as my rears...I still have OEM pads and rotors on mines and I do drive "rather briskly" when traffic and conditions permit. I have EBC Red Stuff pads on my STR and they work great with a lot less dust. I'm going to put them on my XKR as soon as its time to replace the pads. Quick question though, the dealer told me it is "best" and "recommended" to replace the rotors when changing the pad. Do you guys agree?

 

Just in process of doing all new pads and rotors front & back after 50k km

Also had the front calipers sent away to be rebuild as the left hand side was sticking and not retracting the piston

Poor quality so instead of oem I have gone all after market gear

 

Depends on rotor condition. Is it "best"? Sure! You're replacing with an unworn rotor that has more metal on it. More energy absorption ability. Question is do you need it? If your brakes are fading a lot I'd say yes. If you never had any issues and the rotor is well within limits and in good shape I'd say no.

At the microscopic level a used rotor has more "hills and valleys", like a record*, than a new one so break in of the pad takes a little longer. The new pads have to wear to the face of the old disc. New discs quite a bit rougher from machining and the new pad breaks in faster. I hope to go two pad changes per rotor on the XKR. Seems this tank goes through a set of pads every 20k miles or so. 40k miles is a good life for a rotor IMHO.

* for you youngin's that's a round, black vinyl disc with that has the vibrations of music in it's grooves in a circular pattern.