Brake Rotors

[Popeye]

Is it just me, or do shops always want to give you new rotors with every brake job now? When I did my own, I almost never changed out the rotors. Just clean up or resurface with a .005 cut and good to go.

 

[Just_Steve]

Rotors are so inexpensive and made from cheap metal might as well change them. I always find my fronts warped to some extent.

 

[Jerry1]

Every time I've got a brake job in the last couple decades, they replace the rotors. I think they are so cheap these days (both in cost and quality of material) that it's just better to replace them unless you buy a high end third party rotor. A long time ago when I asked, the guy said if he turned them, there wouldn't be enough material left for them to be in specifications. Really? I think they just don't want to waste the time turning them, plus, he was probably right that they would be thin and there'd be added risk of them warping.

 

[davebarnes]

Ever since they got rid of asbestos in brake pads, the recommendation is to replace both pads and rotors.

 

[Popeye]

I guess it doesn’t help when they use the air gun to tighten the lug nuts.
I would think the rear brake rotors might survive once in a while unless those are made even thinner to begin with.

 

[Popeye]

Every time I've got a brake job in the last couple decades, they replace the rotors. I think they are so cheap these days (both in cost and quality of material) that it's just better to replace them unless you buy a high end third party rotor. A long time ago when I asked, the guy said if he turned them, there wouldn't be enough material left for them to be in specifications. Really? I think they just don't want to waste the time turning them, plus, he was probably right that they would be thin and there'd be added risk of them warping.

I wonder if anyone even has the machine to turn them on anymore.

 

[MRG]

Every time I've got a brake job in the last couple decades, they replace the rotors. I think they are so cheap these days (both in cost and quality of material) that it's just better to replace them unless you buy a high end third party rotor. A long time ago when I asked, the guy said if he turned them, there wouldn't be enough material left for them to be in specifications. Really? I think they just don't want to waste the time turning them, plus, he was probably right that they would be thin and there'd be added risk of them warping.

I think there was a technology change. In 76 I ran auto parts, picked up a million of them to be turned and returned. I believe at some time they became cheaper to replace and also became thinner(egg, chicken?) as nobody particularly liked turning them. From the mechanics side they had equipment tied up waiting for a third party, who may be queued. Sure some shops had the equipment, but it wasn't cheap(at least back then).

 

[travelover]

I think there was a technology change. In 76 I ran auto parts, picked up a million of them to be turned and returned. I believe at some time they became cheaper to replace and also became thinner(egg, chicken?) as nobody particularly liked turning them. From the mechanics side they had equipment tied up waiting for a third party, who may be queued. Sure some shops had the equipment, but it wasn't cheap(at least back then).

This. Parts got cheaper, labor got more expensive. My only gripe is the markup on the parts by the shops. Check Rock Auto for the parts prices versus what the shop charges you if you want a good rant topic.

 

[jazz4cash]

Agree that the parts are cheaper (e.g. thinner, wear faster) and the replace vs. repair mindset has taken hold. I have a hobby car which is a 1988 model and I try to keep it as original as possible. I did the brakes myself and went from shop to shop to shop trying to find someone to turn the rotors. I got a lot of disgusted looks for not accepting a new set. I had mic'd them so I knew they had enough metal to be turned. I finally stopped at a local Midas shop and the service manager said she only had one tech that knew how to use the brake lathe and if I left them she would have him take a look when he came in and had time. Probably an old timer! It took about 5 days to get them back and the tech wanted meet me when I came to pick them up. It was about $40 to turn them so still cheaper than replacing.

 

[38Chevy454]

I think as stated the lower cost of the rotors is a big factor. Plus a shop can do a brake job quicker by just replacing rotors with new vs waiting and turning the old rotors. The shop also makes money on the new parts, their price is much less than the price you pay on the bill. So in the end, no shop wants to turn rotors.

 

[MRG]

I think as stated the lower cost of the rotors is a big factor. Plus a shop can do a brake job quicker by just replacing rotors with new vs waiting and turning the old rotors. The shop also makes money on the new parts, their price is much less than the price you pay on the bill. So in the end, no shop wants to turn rotors.

Ding ding. They sure do make money on new parts. When I did that job, everyone doubled the price of the goods, every time they were bought/sold.

 

[Cortina]

Why change ?
If they are warped - change
If they are below minimum thickness - change
resurface ... naah , pads will soon bed in
otherwise (for example : step to disc (rotor in American speak) outer edge) - fit new pads and carry on , but be aware things may take a little while to bed in. I don't quite buy the "they are cheap so change them " argument ... change on the basis of NEED.

 

[Gumby]

Why change ?
If they are warped - change
If they are below minimum thickness - change
resurface ... naah , pads will soon bed in
otherwise (for example : step to disc (rotor in American speak) outer edge) - fit new pads and carry on , but be aware things may take a little while to bed in. I don't quite buy the "they are cheap so change them " argument ... change on the basis of NEED.

Quite right. I install new rotors only when they go below the minimum specified thickness (haven't had a warped one yet). I order the new rotors online and replace them myself. It's not difficult. But then I do virtually all my own auto maintenance and repairs.

 

[travelover]

Quite right. I install new rotors only when they go below the minimum specified thickness (haven't had a warped one yet). ......

Technically, they usually don't actually warp. They develop disc thickness variation (DTV) from the pads rubbing every so lightly over all those miles. You can measure it of course, but usually you'll know that the DTV is excessive by how much the pedal pulsates when you brake. I normally don't do anything to the rotors if the pads are just worn but there is no vibration when braking.

 

[Lakewood90712]

Quite right. I install new rotors only when they go below the minimum specified thickness (haven't had a warped one yet). I order the new rotors online and replace them myself. It's not difficult. But then I do virtually all my own auto maintenance and repairs.

Me too.

I used to let the shops turn on every pad change when I was busy before retirement. Now retired, went back to doing own minor maintenance, in 90K miles 2 sets of front pads, one set of rear.

Using the expensive OEM pads, about 4 hours of my labor total for the 3 brake jobs., has saved about $600 in shop charges. Rotors, still in spec on thickness , not warped. I spent a little over an hour on each pad change, a shop would be at least twice as fast. So the shop would be getting $300 hour for actual labor, and 50% markup on parts too.

 

[Winemaker]

Some vehicles, like my Chevy Colorado, require you to pull front axle to replace rotors. Opens up can of worms bigly! The first time I did it I damaged the ABS sensor cable and wheel bearing.

A lot depends on the type of brake pad you choose. If you use a "platinum" quality pad, it is a harder, tougher pad and is much harder on rotors. If you use a "silver" quality, they are a much softer pad, easier on rotors, but you have to change the pads often That's the tradeoff.

Also, if you have the fancy, nickel /slotted/drilled rotors you may have different wear issues, but being a poor LBYM type, I have no experience with them.

 

[frank]

I just replace pads unless the rotors are really bad. brake pads are cheap and easy to install. some rotors can be a little tricky to replace, some not so bad. I have a 2012 prius that I replaced the pads all around and one rotor. the rotor was the problem it wore the brakes right down to iron because the rotor rusted from the inside. the other three rotors were good, but changed pads all the way around just to keep things even. 2006 silverado 4wd pickup. 53k miles have replaced the front pads 3 times, rotors once, back brake shoes once. chevy is the worse for front brake pad wear I have seen. it seems all the wear goes on the front pads, calipers poorly made and won/t release. prius 92k miles one set brake pads and one rotor. if you think about doing your own work, check out you tube for videos on what is involved.

 

[mountainsoft]

Is it just me, or do shops always want to give you new rotors with every brake job now? When I did my own, I almost never changed out the rotors. Just clean up or resurface with a .005 cut and good to go.

I've always done my own brakes and very rarely change the rotors. If the rotors start to warp or wear unevenly you can usually feel it in the pedal when braking. In that case I'll replace the rotors the next time I replace pads. I have never had rotors turned, I wouldn't even know where to have that done, and wouldn't want to take the time to run to town and have it done. It's easier just to have a new set of rotors on hand while I have things apart.

We have always bought used cars that are 12-15 years old. I usually put new rotors on the first time I work on the brakes, but it's rarely needed after that.

 

[Breedlove]

Kind of funny the better Rotors cheaper are from China , the more expensive and told to be the better ones are thinner and wear out soon

 

[travelover]

Kind of funny the better Rotors cheaper are from China , the more expensive and told to be the better ones are thinner and wear out soon

I don't know that this is true. Certainly no name parts from China are cheaper.

 

[frank]

I don't know about better or cheaper, but I ordered brakes and rotors for my truck from ebay after using the local brand. I put them on and they seem to be doing well. better than the original or local. I also ordered a set of 4 rotors and brake pads for my prius for under 100 dollars and have them on hand in case I have to change them again. when you buy these parts who knows where they originate before they are repackaged.

 

[Lakewood90712]

.................................. who knows where they originate before they are repackaged.

IIRC those low cost auto parts all come from Elbonia .

https://www.urbandictionary.com/define.php?term=elbonia

 

[tominboise]

In the old days, the front rotors and hub were machined from one casting, and the hub also had the wheel bearing races pressed into it. Hence, it was a more expensive component in the first place and it made sense to turn it if required.


New cars by far tend to have unitized front wheel bearings and the rotor is a separate element which is held onto the hub with a couple of screws or similar. The rotor casting is a much lighter element and likely most don't have enough extra thickness to have turning as a viable option.

 

[Bamaman]

I used to drive mega miles, and the company cars ate brakes. I once burned up a set of brake drums on one hill outside of Chattanooga--3 days after new. Thankfully cars now are lighter and seldom have such bad brake parts as they had in 1989.

I now have my own personal cars (5 of them), and do my own brake repairs. I do change rotors usually every other brake job on the cars. My 3/4 ton truck brakes are so heavy and thick that I just turn'em as long as there's still enough metal to meet specs.

One of my cars' brakes were terrible, as I have not been running it regularly. I disassembled the brakes and found rusty brake hardware. A good greasing, and they're as good as new.

 

[ponyboy]

The first problem is, you take your car to a mechanic to change brakes/rotors. its a simple 30 min job.

I just changed my brakes...decided not to change rotors. Big mistake. They were warped. Had to pull them off and replace with new. New rotors cost $71 out the door from advance. They're cheap...just replace them when you change the brakes, for those who like to get their hands dirty. There's nothing like new brakes/rotors...nice and smooth!

Also...My pads werent that bad but I was going in for inspection and didnt want to risk them trying to change them. 90,000 miles...I could have pushed them to 120,000 miles!