Warped Rotors and Semantics

"AMGtech - now with more recalls!" (amgtech) 03/13/2016 at 15:08 • Filed to: Warped rotors

13

31

Ok fine, I get it. You’ve all read that !!!error: Indecipherable SUB-paragraph formatting!!! article and now you’re all brake wear experts. Cool. Let’s not discount the merits of that article, it really has some good information. But let’s stop with the bullshit.

Maybe rotors warp and maybe they don’t. That isn’t the point here. The point is that rotors are generally measured for runout and thickness variation if they’re suspected of causing a vibration. Whether the problem is deposits, hot spots, or (god forbid) warping, one of those two measurements is how you’re going to make your diagnosis.

Let’s assume the problem is deposits. 99% of the time you won’t be able to see them. So you measure and find both runout and thickness variation. In my experience, you can’t make this go away just by doing a few (or even quite a few) hard stops to “scrub” the material away. It just gets worse or doesn’t work at all. The only times I’ve seen this work is if it’s just light surface rust but that usually causes more noise than vibration. So it comes down to resurfacing or replacing (pads too).

What if the problem were hot spots? You can almost always see these, especially if you know what to look for. But it’s still a good idea to measure. So you do, and find both runout and thickness variation. Huh. Just like with deposits. But you can't machine these out. So it comes down to replacing, pads and rotors. Just like with deposits.

And if those rotors are actually warped? They will look fine to the naked eye (grooves and lips don’t necessarily indicate problems, just normal wear). Just like deposits. Weird. So it comes down to resurfacing or replacing.

Resurfacing is very much hit or miss and rotors are usually cheap enough that they outweigh the pros of resurfacing. So let’s just replace them. And for the sake of this whole spiel, let’s assume wheels have been properly torqued and the hubs are clean and true.

So how do we differentiate between deposits, hot spots, and warping if we can’t see any problems? Beats me. You certainly can’t make that differentiation in most shops, garages, or driveways. Even the correct repair is the same. Trying to make that differentiation is not worth the effort. Trying to explain the difference between those three problems to your customer, mother, brother-in-law, sister, best friend is not worth the effort. Saying the rotors are warped is a general and all-encompassing term.

If we’re really going to argue semantics every time someone says their rotors are warped, then we as automotive enthusiasts and professionals have a lot of work ahead of us. Let’s start punching the idiots who refer to engines as motors, since motors are electrical components. Let’s put dog crap on the hood of the car of anyone who says their car threw some faults and the CEL came on, cars don’t throw things and it’s technically a MIL (malfunction indicator light). And anyone who refers to a crankshaft position sensor as a CPS (it’s CKP, camshaft position sensor is CMP) we can force to only read Alissa Walker articles and use public transportation.

Stop the bullshit. Stop arguing semantics over warped rotors.

Alfalfa > AMGtech - now with more recalls! 03/13/2016 at 15:16

2

Shane MacGowan's Teeth > AMGtech - now with more recalls! 03/13/2016 at 15:20

2

But, but... how am I supposed to distract myself from my unfulfilling life and feel superior to others?!

AMGtech - now with more recalls! > Shane MacGowan's Teeth 03/13/2016 at 15:24

10

Buy a BMW and drive like an asshat?

Matt Nichelson > AMGtech - now with more recalls! 03/13/2016 at 15:47

0

Damn, that’s where I messed up! I bought the BMW, but I didn’t follow through.

That's gonna leave a mark! > AMGtech - now with more recalls! 03/13/2016 at 16:17

0

The English are going to take offense as they refer to all cars as motors.

AMGtech - now with more recalls! > That's gonna leave a mark! 03/13/2016 at 16:25

0

Shit. Well let’s just all switch over to Latin and ban all types of slang and language evolution.

His Stigness > AMGtech - now with more recalls! 03/13/2016 at 16:50

1

I’m sure you’re referring to my ranting of “throwing” codes, which is fine. I admit it’s an unfounded hatred and I get pissed off easily.

After I read the StopTech article I tried to talk to my old boss about it, but because he’s older than 60 he essentially put his fingers in his ears and starting making noises. I kind of get that, though. People have their pre-conceived notions and they’re very hard to change, which is why I agree with your argument: stop arguing over what amounts to semantics.

On a related note, how often do you have to deal with customers since you work at a dealership and have people employed for the specific purpose of dealing with them so you don’t have to? I only worked at dealerships for a little while, so I can’t answer that. As an independent technician though I deal with them on a quite a regular basis, and that was before I started doing service writer work.

TheOnelectronic > AMGtech - now with more recalls! 03/13/2016 at 16:51

3

See, this is where being fairly ignorant comes in handy. I can’t argue semantics if I don’t even know what I’m talking about in the first place.

AMGtech - now with more recalls! > His Stigness 03/13/2016 at 17:27

2

Lol yeah. No offense intended! I just got going on a rant.

Let’s say I talk directly with customers at least 3-5 times a week on average. Which is more than most techs because I’m a team lead and my service advisor has some shortcomings in the getting information department.

AMGtech - now with more recalls! > TheOnelectronic 03/13/2016 at 17:29

1

That ol’ cliche, ignorance is bliss.

His Stigness > AMGtech - now with more recalls! 03/13/2016 at 17:52

0

No offense taken, I understand completely. I love your ABC post by the way, I know how frustrating that can be, even though I’m not flat rate. My biggest pet peeve is when I have people standing over me while I’m working. Or worse, ask me questions when I literally have my head in an engine. Can you not seem I’m busy right now?!?!

Wow, that seems like quite a lot. Although I do understand having a bad service writer. In my time working at dealerships, and also dealing with them as a customer, I’ve only found one good writer.

Where I’m at now, though, my boss is the writer, and he has no fucking clue which way is up, so it makes everything a million times harder. To make matter worse, though, the bookkeeper will occasionally schedule people and write down what they brought it in for, and she literally knows nothing about cars, so it’s even worse. A few weeks ago she wrote down something so incomprehensible my co-worker and I had no idea what to do. I think there are few things more embarrassing than having to ask a customer explain his problem a second and third time.

I want to open my own shop so things are done right, but finding other good techs (like yourself) is actually quite hard, that’s the only thing that has stopped me so far.

AMGtech - now with more recalls! > His Stigness 03/13/2016 at 18:30

1

It’s alright. It’s usually for very strange or difficult to duplicate issues. That way I can get the customer’s story directly. My advisor isn’t bad, he just neglects some key questions occasionally. I think great advisors are just as hard to find as great techs.

With the right coaching and patience, most people can improve. And with getting the story from the customer’s again, try to ask in such a way that saves face, “we’re looking at your car right now, but we were hoping you could tell us everything again, just to be sure we’re not missing anything”.

If you want to open your own shop, more power to you. It’s not something that interests me. Too much cost and work involved with too high of a risk. Seriously, if you go for it, good luck and I wish you success.

shop-teacher > AMGtech - now with more recalls! 03/13/2016 at 18:39

0

Sounds reasonable to me!

His Stigness > AMGtech - now with more recalls! 03/13/2016 at 18:52

0

Yeah I definitely understand those types of problems. But my boss and the bookkeeper are missing key details like the car smokes in the morning, or it idles like shit till it’s warm, sometimes. Those are things even a crappy advisor knows to write down and tell us because it’s important. I had that happen just the other week, and I didn’t know it the car was idling like crap till it came back in after it had stalled while driving and that was after I did a bunch of maintenance work on it. I was so irritated because my boss should have told me. It turned out the idle issue was just the symptom of impending failure and had he told me before the customer never would have stalled on the freeway. So while I did nothing wrong, “we” looked like idiots in the eyes of the customer. This failure was also a teachable moment for the customer to learn that a proper oil change with the proper oil at the proper interval (not 15k) could have prevented the problem. But my boss never told him that because he’s kind of retarded.

Unfortunately there’s no changing his habits. He’s been “working” on cars since the 90's when he lived in Denmark and has owned two shops before this, but this is the first one he’s had to run by himself. He does stupid things like use customer’s cars as his own and never, ever drives his own cars. And apparently a few customers have gotten pissed at him, but he still does it. And it’s not like he’s driving cars that need to be driven. Nope. A car with a scratched sun roof doesn’t need to be driven. Or a car that’s literally falling apart and the owner is trying to sell and we are selling it for them (HA!), that doesn’t need to be driven. It’s beyond infuriating.

But opening a shop is scary, and there is a shit load of effort involved in it (if you want to keep it open), with very little reward.

That's gonna leave a mark! > AMGtech - now with more recalls! 03/13/2016 at 19:15

0

Sorry, comment was meant to be funny.

AMGtech - now with more recalls! > That's gonna leave a mark! 03/13/2016 at 19:16

0

Sorry mine was too. Sarcasm didn’t really come through I guess.

His Stigness > AMGtech - now with more recalls! 03/13/2016 at 23:23

0

I don’t know if you’ll know the answer to this, but I’ll ask anyways:

The brake switch for my W202, do you know if Febi Bilstein makes it? I’ve only ever put Genuine MB switches in it, but they always fail in less than a year and only a few thousand miles of driving. The OEM is $19, but the Febi one is only $7.

AMGtech - now with more recalls! > His Stigness 03/13/2016 at 23:44

0

Not sure. I’ve never had a replacement MB one fail. Are your new ones black or blue? The blue ones are updated. Otherwise, screw it, try the cheap one.

His Stigness > AMGtech - now with more recalls! 03/13/2016 at 23:47

0

I’ve only gotten black ones, but the picture on WorldPac is blue now for the MB one, and that’s the first time I’ve seen that. So get the genuine MB blue one?

AMGtech - now with more recalls! > His Stigness 03/14/2016 at 00:05

0

Black ones were the old, recalled version (ok, so there’s a handful of black ones that aren’t under the recall). So that’s probably your problem, the black ones suck.

His Stigness > AMGtech - now with more recalls! 03/14/2016 at 00:33

0

Oh well then that makes sense because I’ve seriously gone through a handful of them in less than 20,000 miles. I’ll order a blue one and keep it for when the black one I just put in fails in a few months lol.

Mattbob > AMGtech - now with more recalls! 03/16/2016 at 11:56

0

V12 Jake- Hittin' Switches > AMGtech - now with more recalls! 03/31/2016 at 22:26

1

Look at the tags on the post, the Merc isn't going anywhere. What do you think of a RENNtech ECU/TCU reflash?

AMGtech - now with more recalls! > V12 Jake- Hittin' Switches 03/31/2016 at 23:02

1

Awesome. I always forget about the tags. I’ve had very good experience with RennTech products. Their improvement in performance is pretty amazing on turbo cars and I haven’t seen any reliability or failures related to them. Totally worth it IMO.

V12 Jake- Hittin' Switches > AMGtech - now with more recalls! 03/31/2016 at 23:16

0

Some people say that the722.6 transmission will pop with any added power. Is this true or just a myth.

AMGtech - now with more recalls! > V12 Jake- Hittin' Switches 03/31/2016 at 23:27

0

It’s possible. More likely if services haven’t been done every 40k. But, you have a V12. Those get a lot of upgrades over standard transmissions, so you might be ok. But it definitely wouldn’t be a bad idea to budget for a performance rebuild down the road.

V12 Jake- Hittin' Switches > AMGtech - now with more recalls! 03/31/2016 at 23:31

0

My thoughts exactly. From this point forward when things fail they will be replaced with performance bits. So RENNtech transmission internals, intercooler pump, ect. And I really want some W220 S65 wheels too. Can dealers order those?

AMGtech - now with more recalls! > V12 Jake- Hittin' Switches 03/31/2016 at 23:35

0

Good plan. I like to do the same, depending on the part and car. I believe those wheels are still available, probably not cheap though, which I’m sure you’re already aware of :)

V12 Jake- Hittin' Switches > AMGtech - now with more recalls! 03/31/2016 at 23:39

0

Yes... But they're my favorite wheels on any car ever. Thanks again for all the help you've been since the start.

AMGtech - now with more recalls! > V12 Jake- Hittin' Switches 03/31/2016 at 23:41

0

No problem, happy to help. Make sure to let us know what your car needs this time around.

V12 Jake- Hittin' Switches > AMGtech - now with more recalls! 04/01/2016 at 00:17

0

Of course ;)