11-27-2019, 10:25 AM | #1 |
New Member
1
Rep 9
Posts |
CPO Question re: brake life
Just took my CPO X3 to a different dealer than I bought it from due to some concerns I had with Dealer #1's ability to deliver on their promises.
When I took my car to Dealer #2, they put my key on their reader and it put out a report showing the car's status, warranty info, etc. On this report I noticed that it said my remaining brake life on front was 8k mi, and rear brake life was 14k mi. I just bought the car as CPO wit 28k mi a month or so ago, should Dealer #1 have done anything with getting fresh brakes on the car or is this within range. Again, just asking because Dealer #1 has been terrible with followup and has given me zero reason to trust anything they say they've done or say they are going to do. |
11-27-2019, 10:51 AM | #2 |
Lieutenant Colonel
829
Rep 1,933
Posts |
These cars use 'Conditioned Based Maintenance" system; mileage counters to give the owner an idea of when to perform maintenance - of the brakes, engine motor oil, etc. These are mathematical formulas programmed into the car's software that interpret data from the cars sensors (speed, engine RPM, acceleration, etc., etc.) to drive these 'countdown' counters, such as the one you're seeing for your brakes. So it's an approximation of brake life, not a physical measurement of the brake pad or rotor thickness. CBM approximates change intervals by estimating your driving 'style' - if you do lot's of city stop/go these counters 'count down' at more rapid clip than they do for a person who does extended open-road driving.
BMW brakes have go/no-go wear sensors on the pads - when the pads get down to pretty minimal remaining material/thickness the wear sensor is 'triggered' and you'll get a warning on the iDrive that the pads require changing very soon. The only way to KNOW how much brake rotor and pad material remains (i.e. percent of brake life) is to physically measure the thickness with a pair of calipers and obviously compare those numbers to spec's for new pads/rotors. I'm not certain the parameters BMW uses to 'qualify' a car as CPO - obviously there is inspection of the brakes, I would presume it's physical measurement. Perhaps a good question to ask the Dealer. Hope this helps/Bill Last edited by Wgosma; 11-27-2019 at 11:01 AM.. |
Appreciate
1
bpwj7695.00 |
11-27-2019, 10:56 AM | #3 |
Private First Class
95
Rep 184
Posts |
My dealer gave me a CPO Vehicle Inspection Checklist when I purchased my 320 that had 32k miles on it. It shows the original pads had 6mm left on the fronts and 7mm on the rears. Someone wrote "Good" in the box under Rotor Condition. It also states the next service for front brakes was in 24,855 miles and the rear in 37,282. As far as I know it still has the original pads and rotors. I have 55k miles now.
I guess 6-7mm of pad left is acceptable for the CPO process. Wonder how much pad was left on yours when you bought the car. |
Appreciate
0
|
11-27-2019, 11:02 AM | #4 |
Private First Class
95
Rep 184
Posts |
Oops, forgot I was on the X3 forum and not the F30 one.
Same report for my wife's X3 shows 8mm on the fronts and 6mm on the rears. The vehicle had 51k miles when we purchased it. They did not change them out when we purchased as CPO. |
Appreciate
0
|
11-27-2019, 11:23 AM | #5 |
Colonel
1233
Rep 2,928
Posts |
I think dealers may set their own specs for pads an tires as to what meets the CPO criteria. Half worn tires will pass. You really need to know your pad thickness. Miles means nothing because driving styles vary, and if the miles you were given was just from the counter on the cluster, that is pretty much utterly useless info.
|
Appreciate
0
|
11-27-2019, 09:08 PM | #6 |
Brigadier General
3434
Rep 4,100
Posts |
Agreed and agreed. New pads are something like 10+mm thick and normal advice is to replace them around 2 or 3mm at the latest. You can figure out where you are in between these and do what's needed accordingly. Thickness is easily measured w/ the right tools (i.e. flashlight and ruler).
|
Appreciate
0
|
11-28-2019, 07:33 AM | #7 |
Enlisted Member
10
Rep 45
Posts |
I believe the BMW CPO standard for brake pads is if there is 50% of the pad left they are good to go, some dealerships may have their own stricter standards, but I think 50% is the minimum !
__________________
Doug
2019 BMW 430 XI Grand Coupe, White, Black leather interior 2016 BMW X3, 28d, Mineral White metalic, Oyster Nevada leather interior. |
Appreciate
0
|
12-01-2019, 08:12 AM | #8 |
Second Lieutenant
24
Rep 253
Posts |
Over the last 2 years my brakes have reported as low as 3100 miles to go and as much as 3900 miles to go. Currently 3700 miles. Long road trips can bump it up.
I've been told by tire place (I asked when I had tires rotated) and I apparently still have plenty of pad. I'm at just over 79,000 miles. |
Appreciate
0
|
12-01-2019, 08:27 AM | #9 |
Brigadier General
3434
Rep 4,100
Posts |
|
Appreciate
0
|
12-03-2019, 07:55 AM | #10 |
General of the Space Forces
179
Rep 729
Posts |
The computer reading on brake pad life is just an estimate based on a formula and the miles/speeds/etc the vehicle has been through since the last pad change/reset. Actual brake pad wear has to be measured, which is what they do for CPO...as long as they have more than some minimum thickness they wont change them.
__________________
Current: 2020 X5 x40i M-Sport, Arctic Grey Metallic / Ivory White, Executive Package, Luggage Compartment Package, Integral Active Steering, Tow Package, Parking Assist Package, Driving Assist Package, M-Sport brakes, Tux Mats
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|