Jeep Garage  - Jeep Forum banner

1 - 15 of 15 Posts

·
Registered
2018 Jeep Grand Cherokee High Altitude
Joined
·
195 Posts
Discussion Starter #1
2018 High Altitude with the HD brakes with 44k km (27k miles)

They are claiming that they should be changed as there has been a color change and will result in reduced braking. I forget the terminology they used, but seems like snake oil to sell me some new rotors. Looking for advise. ;)

Mileage seems a bit low to need new rotors, but I thought I would ask. I included a picture (which may or may not be useful).

But while I am at it, is it a 11mm hex head driver to remove the front calipers (T45 for the rears)?


232032
 

·
Registered
2018 Jeep Grand Cherokee High Altitude
Joined
·
195 Posts
Discussion Starter #3
If they are glazed, but still within thickness specs, they can easily be cleaned.
Thank you, that may have been the term they used.

Does the old method of sand paper still apply for removing the glazing?
 

·
Registered
Joined
·
92 Posts
It should. I've always used abrasive discs on a drill. Uneven pad deposits on rotors can also mimic warpage, which leads to a lot of un-neccesary premature rotor replacement.
 

·
Registered
Joined
·
22 Posts
Depending on budget & time. I've had local parts store turn rotors. IIRC, $20/rotor. The last set I did, I didn't have a garage to do the job so I purchased new set of drilled/slotted rotors & pads. Much easier & takes the guesswork, time back & forth to store & was an upgrade.

27k is a short time to need new rotors, but it also depends on your driving style.
 

·
Registered
21 JGC Overland and 18 Audi SQ5
Joined
·
17 Posts
Do you feel any reduced stopping power or steering wheel shaking when braking ?

What you see is material from the ceramic brake pads, they create friction by depositing a thin coating of the ceramic pad onto the rotor and when you apply the brake that material creates friction with the pad to get you the braking resistance.

This is why ceramic pads don't create a lot of brake dust on your wheels and your rotors show no wear at the outer edges.

With a Semi-Metallic pad the rotor would look like it just came off the lathe because when you apply brakes it is actually removing metal from rotor surface to create friction. you also get a lip at outside edge of rotor where pad does not hit and you get a ton of brake dust usually.

Your rotors look great to me !
 

·
Registered
WK2 2014 Jeep Grand Cherokee Limited Sport Utility 3.6
Joined
·
116 Posts
27k miles I literally did last summer.. seems way too soon to change them, rotors seem fine IMHO, if you wanna sand them for the peace of mind you can always do that, I would personally just replace nice new pads, even maybe rotate the rotors to see if there is any difference in shaking or stopping power but no need to pay for new rotors yet.
 

·
Registered
WK2 2014 Jeep Grand Cherokee Limited Sport Utility 3.6
Joined
·
116 Posts
27k miles I literally did last summer.. seems way too soon to change them, rotors seem fine IMHO, if you wanna sand them for the peace of mind you can always do that, I would personally just replace nice new pads, even maybe rotate the rotors to see if there is any difference in shaking or stopping power but no need to pay for new rotors yet.
oh, the front is 11 hex, and the back is 7 hex.. the back has a very tight space, hopefully, you'll be able to put the ratchet in there. I used a regular long hex 7 key (amazon 6$ ) :)
 

·
Registered
Grand Cherokee
Joined
·
4,003 Posts
Semi-Metallic pads, and Ceramic pads have metal in them, that can result in the rotor surface looking a little different than the past when the pads would polish the rotor surface to bright shiny silver. I don't know if it leaves some of the metal, ceramic or carbon behind in the surface of the rotors or if its just the surface finish it creates on the rotors, either way, I have seen different kinds of pads leave different colors or finishes on rotors and not experience any difference in the brakes at all.

Modern brakes can cause hot spots in the rotor, either a flaw in the casting or high heat, the metallurgy can be changed and a spot hardens on the rotor, it will be different color as well. Turning the rotor won't fix this either, you have to replace the rotor, its rare, but I have had it happen on a car years ago. Decades ago, pads were soft and rotors were hard, the rotors would last longer than the life of the car, folks could get rotors off worn out junked cars.... ....as time has gone on, and more performance but also quiet is demanded of the brakes, the pads have gotten harder and rotors softer (a lot of manufacturers intentional use softer iron for rotors to keep noise down) and its to the point you often have to replace the rotors with the pads.... ....as well, cars are lasting longer also....

You replace rotors because they have worn down past their minimal thickness, they deform (often called warped), wear unevenly, glazing can be fixed, but I see modern brakes with rotors a different tint or surface finish than polished silver all the time, and different pads creating a different tint or surface finish on the same rotor, I wouldn't judge the rotors bad on that appearance alone.
 

·
Registered
GC TH
Joined
·
477 Posts
Do the same procedure you’d use to break in a new set of pads and rotors. Find a road with no one around and do several hard braking runs from 60-10. Never come to a complete stop, and drive around for a few to cool everything off before stopping completely.
 

·
Registered
2018 Jeep Grand Cherokee High Altitude
Joined
·
195 Posts
Discussion Starter #11
Do you feel any reduced stopping power or steering wheel shaking when braking ?

What you see is material from the ceramic brake pads, they create friction by depositing a thin coating of the ceramic pad onto the rotor and when you apply the brake that material creates friction with the pad to get you the braking resistance.

This is why ceramic pads don't create a lot of brake dust on your wheels and your rotors show no wear at the outer edges.

With a Semi-Metallic pad the rotor would look like it just came off the lathe because when you apply brakes it is actually removing metal from rotor surface to create friction. you also get a lip at outside edge of rotor where pad does not hit and you get a ton of brake dust usually.

Your rotors look great to me !
Thank you for the input and to answer your question, no, I have not noticed any reduced stopping power or shaking.

The dealer offered me a free piece of mind inspection and this is pretty much the only thing they said (well and an air filter). Didn't seem right to me that the rotors would need replacing so soon and questioned them about it. Needless to say I walked, not going to spend money when I didn't notice any issues, but thought I would ask just in case. :)
 

·
Registered
Joined
·
47 Posts
The dealer is always going to say you need rotors......you could look for a water fountain and they are going to say you need brake rotors, oil change, whatever the service special du’jour is.

want WiFi? You need a transmission

Coffee? Your engine is overheating.

Where the restroom?......let me show you this all new 1995 Dodge Intrepid, that latest in cab forward technology and cabin design.......vehicles are way different but the sentiment is the same.
 

·
Registered
WK2 2014 Jeep Grand Cherokee Limited Sport Utility 3.6
Joined
·
116 Posts
The dealer is always going to say you need rotors......you could look for a water fountain and they are going to say you need brake rotors, oil change, whatever the service special du’jour is.

want WiFi? You need a transmission

Coffee? Your engine is overheating.

Where the restroom?......let me show you this all new 1995 Dodge Intrepid, that latest in cab forward technology and cabin design.......vehicles are way different but the sentiment is the same.
Can I get fries with that? Sure but your blinker liquid is running low.. that will be 489.99 plus Tax..
 

·
Premium Member
2018 Summit
Joined
·
179 Posts
As previously posted, if there is warpage, then replace the rotors and pads; if the braking is smooth (no vibration when brakes are applied) they should be OK.

I replaced the rear brakes on my wife's 2018 Summit last fall with fewer miles than what the OP has... There was a very noticeable vibration from the rear brakes when applied... enough to wake the dog from a sound sleep. With just less than 21,000 miles, I figured the dealer would notlikely cover the job under warranty, so I bought a set of the best pads and rotors available at NAPA and went to work. The brake hardware (slide pins, etc.) was in perfect condition, but the pads and rotors were worn and nasty.

The improvement was immediately apparent, and has been perfect ever since. I am still wondering why the rears went bad before the fronts (which are still OEM's.
 

·
Premium Member
2018 Summit
Joined
·
179 Posts
Update: I just looked, and replaced the original rear brakes at just less than 21,000 miles o_O... I am attributing the problem with those to corrosion from the stuff that is applied to the roads in central upstate, NY during our snow season. I swear, they "pre-salt" the roads even before rain as well as before any predicted amount of snowfall. As a result, I need to keep a closer eye on all four wheels' brakes.

Last evening, on the way to dinner and after driving ~20 miles, my wife mentioned she was hearing a chirp at low speeds... no worse when brakes are applied... seemed to be from the front. I checked the front rotors; the left looked good and the right had some discoloration and a slight "ridge" (not yet sure what the back side looks like). At ~27,000 miles, it appears the OEM front pads and rotors will soon need to be replaced with something better in a solid/vented rotor and maybe ceramic pads. .
232171
IMG_2112.jpg
 
1 - 15 of 15 Posts
Top