[sdbob]

I have a 2015 GMC 2500HD I bought new. It has 63500 on original rotors and pads. I'm getting vibration when braking hot. I'm thinking new rotors or can these be cut? If new which brand to buy since china is the source? I leaning toward new rotors and pads just would like same longevity as originals. Any opinions?

[Chief of the 60's]

I found out years ago that it doesn't matter if you buy cheap rotors or expensive ones, they're all crap so don't spend a lot of money.

I like turning mine, but I have my own brake lathe. Good luck finding someone to turn rotors these days, cheap rotors all but killed that business.

Now, you could do what I did. Go to one of these shops that has a lathe sitting in the corner covered in dust from not being used in years and see if they will sell it. I paid $250.00 for my Ammco lathe complete with all attachments and workbench.

[Bills Auto Works]

It has been quite a while since I bought them, but I have cross drilled & slotted rotors from Summit Racing on both my 2500HD GMC & my 3500 Chevy along with a pad upgrade for towing & do not have any kind of hot braking issues. Not sure of brand, but they could be Summit House Brand.
I could not tell you about longevity as far as mileage though because brakes last me hundreds of thousands of miles since I drive cross country transporting & go for hours & hours with ever touching them.

God Bless
Bill
https://www.jalopyjournal.com/forum/...closed.614419/

[OG68]

I bought at Napa. Fleet and Police line. I pull a 7000# trailer quite often in the mountains and they've held up well.

[dataway]

Your lucky to have gotten that many miles out of them. Love my 2011 GMC truck but I had to replace the entire front brake system at about 40K miles, and I did it again at about 80k miles. Rotors totally rusted, calipers starting to seize. Granted I'm in NY with lots of salt on the roads.

Your parts are probably more expensive than my 1500 parts ... but I've found it easier just to replace everything with new aftermarket parts. It's a routine now, about every 4 years I replace the rotors, calipers, pads and hoses, very affordable on the 1500 series.

In 2001 GMC 1500s had rear disk too ... horrible, you'd get about two years out of them ... they actually went BACK to drums in the rear it was so bad. So much salt gets thrown on the rear disks in northern climates that they would just disintegrate in two years.

As Chief says .... I haven't found any appreciable difference in quality between the average part and the "premium" brake parts. You might get an extra six months to a year before they start to rust away because of better coatings, that's about it. Premium pads do see to work better and last better though.

[sdbob]

Thanks guys. Reading about depth of heat treat shallow on some, better on others. I was thinking oem parts. Then like you said Bill- Summit. I'm planning my moves as I always do.

[FrankieT/A]

A lot of people don't turn rotors anymore because brand new they are already close to minimum spec. (Printed somewhere right on the rotor, sometimes on the edge).
The vibration you are referring to is called pulsation. If you have pulsation chances are there will not be enough meat to turn them (Resurface).

I happen to have a 2001 Silverado (360,000 on the clock and I've never had a valve cover off, still has factory freon in it) with rear wheel disc. I have no problem with mine except i go through rear pads 3 times as often as fronts which is not the norm. Usually two sets of front to one set of rear.

I owned a 2011 Sierra and it did have rear drum. Currently I have a 2015 Sierra Denali with four wheel disc. My original front rotors rusted away to nothing by the time I had 70,000 miles. I'm in south Florida so no salt. I replaced the rotors with top of the line Wagner rotors and ceramic pads (for cleanliness) and no problem since(I now have 105,000). I pull my car trailer with car 1300 miles 5 times a year and no issues.

My advice would be buy good rotors and pads and sail on.

[ID67goat]

I have had good luck with Powerstop brand rotors. They usually sell in a kit with pads included. They are drilled/slotted and cad plated to avoid rust.

Used them on 4x4 7.3 Excursion which frequently towed 7K-10k and never had an issue with their pads or rotors.

[hgerhardt]

Wow, that salt is amazingly destructive! We have a 2003 1500 which we bought new and has 98k miles on it today. Replaced the original pads at 85k, both frt and rr at the same time. All the brake parts still look pristine, but we're in SoCal.

Do have some of that rotor runout too, but can't see any sign of that on the rotors. Also virtually no wear on the rotors, probably thanks to that surface treatment GM said they did to these trucks.

[Sirrotica]

FWIW, they've cut their using rock salt here in Ohio and have been using liquid calcium chloride to pretreat the roads in anticipation of oncoming snow storms. It's much more destructive than just plain old rock salt is because it's concentrated.

I'm not sure if all states have switched over to liquid calcium chloride, but Ohio has, and I noted how much more my old truck rusts over a winter than when they only used rock salt. One thing the states always have enough money for is to put plenty of de icer on the roads to ruin any ferrous metals on vehicles.

I just purchased a complete set of Power Stop rotors and ceramic pads for all 4 wheels on my 99 GP so I have no idea if the plated rotors will inhibit rust yet or not. The Power Stop stuff looks nice out of the box, but we shall see how it stands up to the next Ohio winter.

[fyrffytr1]

I worked for O'Reilly Auto parts until about 2019 and we were turning rotors almost every day. Like has been said the minimum thickness is stamped on the inside of cap most times. Front should be 1.181"s new, discard thickness is 1.102" and minimum thickness after turning is 1.122". We used specific brake calipers to measure them. And, as already stated here the OEM rotors were coated to make them last longer but yours have probably worn that coating off.If your rotors are not grooved and they meet the turning requirements I would have them turned. You will probably get about half the original mileage on them.

[fyrffytr1]

I have to amend my last post as I don't know what exact truck you have. Is it an Lt? What motor?

[sdbob]

Sierra 2500 HD with 6.0. I have it inspected twice a year according state law.still original pads.

[Sirrotica]

Bob, it could also have a sticky caliper causing the rotors to warp from dragging, it's about in the correct age, and mileage to possibly have a caliper that isn't frozen completely, but is dragging slightly, and overheating the rotor. When I bought my 93 K3500 (2010) I rebuilt both front calipers because they were hanging up. The previous owner had just put 2 new rotors on it, and I noticed the one front wheel dragging. I didn't want to ruin the new rotors so they got kits in both sides.

Maybe jack each wheel up and see if one has more drag than the others, before you start taking the brakes apart. If you find one wheel dragging, I always either rebuild the axle set of calipers or replace them both. Usually the other one will hang up in short order if you only do one. You may even be able to discern which wheel has warped the rotor by jacking it up and spinning each by hand. If it's bad enough you'll feel the difference in one complete revolution.

One other thing is, cutting rotors usually makes them more prone to warping again, especially on a rotor with smaller mass. When cars downsized in the early eighties and the cooling fins were taken out in favor of solid rotors on smaller applications, that is when I saw more warped rotors. Your truck would have finned rotors, so they are at least in the category that they could be turned because of the shear mass that a 3/4 ton truck has.

I worked at a Buick dealer in Erie in the mid eighties, and we had tons of the later model Buicks come in with warped rotors and drums for state inspections. The smaller solid rotors were more prone than the larger finned styles were.

Unlike many state inspection stations in PA, I road tested every car that I inspected, and by doing so would find vehicles with warped rotors and drums that the owners just became accustomed to as it usually happens slowly, and some people just ignore it.

[SRR]

Originally Posted by Sirrotica

Bob, it could also have a sticky caliper causing the rotors to warp from dragging, it's about in the correct age, and mileage to possibly have a caliper that isn't frozen completely, but is dragging slightly, and overheating the rotor. When I bought my 93 K3500 (2010) I rebuilt both front calipers because they were hanging up. The previous owner had just put 2 new rotors on it, and I noticed the one front wheel dragging. I didn't want to ruin the new rotors so they got kits in both sides.

Maybe jack each wheel up and see if one has more drag than the others, before you start taking the brakes apart. If you find one wheel dragging, I always either rebuild the axle set of calipers or replace them both. Usually the other one will hang up in short order if you only do one. You may even be able to discern which wheel has warped the rotor by jacking it up and spinning each by hand. If it's bad enough you'll feel the difference in one complete revolution.

One other thing is, cutting rotors usually makes them more prone to warping again, especially on a rotor with smaller mass. When cars downsized in the early eighties and the cooling fins were taken out in favor of solid rotors on smaller applications, that is when I saw more warped rotors. Your truck would have finned rotors, so they are at least in the category that they could be turned because of the shear mass that a 3/4 ton truck has.

I worked at a Buick dealer in Erie in the mid eighties, and we had tons of the later model Buicks come in with warped rotors and drums for state inspections. The smaller solid rotors were more prone than the larger finned styles were.

Unlike many state inspection stations in PA, I road tested every car that I inspected, and by doing so would find vehicles with warped rotors and drums that the owners just became accustomed to as it usually happens slowly, and some people just ignore it.

A rotor is essentially a heat sink. If you remove more material from it there is less to absorb the heat. Our old school vehicles had lots of meat on them and it wasn't as much of an issue. I would just replace the rotors, check for caliper binding and replace the pads with good quality parts.

[fyrffytr1]

Originally Posted by sdbob

Sierra 2500 HD with 6.0. I have it inspected twice a year according state law.still original pads.

You are looking at about $350.00 for a pair of AC/Delco rotors. Even O'Rilly store brand rotors are only about $20.00 cheaper for the pair.

[sdbob]

Thanks guys for all the information makes sense once you think about rotors and mass. Yep we have salt,antiskid,and liquid chloride. Nasty stuff to keep people safe.

[skipp65]

Caliper pins are probably frozen causing constant pressure on the rotor. Those rotor aren’t cheap and putting the best most expensive ones on isn’t really a benefit. Why do you need it inspected twice a year?

[Sirrotica]

Originally Posted by skipp65

Caliper pins are probably frozen causing constant pressure on the rotor. Those rotor aren’t cheap and putting the best most expensive ones on isn’t really a benefit. Why do you need it inspected twice a year?

I was wondering the same thing......

I moved from PA in 1999, and it was still once a year, down from twice a year when I first started spinning wrenches as my profession (1971). I thought maybe they went back to twice a year since I moved away, and surrendered my inspection license.

FWIW, I finished the Power Stop kit install, (4 wheel ceramic pads, and drilled and slotted rotors, $235 amazon) yesterday on my 1999 GP, bedded the brakes in as per their instructions. I did have one caliper pin that was corroded that probably caused the rear rotor to warp on the drivers side.

I drove the car this morning about 30 miles and the Power Stop brakes are working very well. Nice thing is no cold metallic grinding noise due to the semi metallic pads that were on the car in the first couple of stops. It should also do away with the rusty powder residue on the wheels not having semi metallic pads any longer.

Power Stop on amazon looks to be about $350 for a 2015 Silverado 2500 for new drilled and slotted rotors, and ceramic pads. You could add new calipers to the kit too, or buy them locally, and of course there's the option of rebuilding the OEM calipers too, (which I prefer to do myself). I've gotten too many reman calipers that were bad right out of the box for me to trust someone else's work. I usually try to buy new ones if the OEMs are too far gone for rebuilding, as opposed to remans for these reasons.

[sdbob]

Oops mental lapse, old memories of twice a year. Yes just once a year. No emissions though being 2500. Thanks I'm losing it!