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View Full Version : does new rotors = new pads?



PhilipJCaputo
04-18-2005, 09:18 AM
I'm thinking about ordering new front rotors today from BMA (probably brembos, unless someone can convince me otherwise)

I put on a new set of pads in the fall, and I'm sure they still have lots of life in them, but I'm sure they've formed a comfort fit with the old rotors...

I don't want to put the old pads to new rotors and cause the new rotors to get grooved early on...


So do I spend the extra 50-60 bucks and just buy new pads too?? I'd rather spend as little as possible, and don't want to take the old pads off before their used up.

Jose
04-18-2005, 09:35 AM
New rotors equalls to new pads. The old pads will be worn in already to the old rotors.

granit_silber
04-18-2005, 10:16 AM
I'm thinking about ordering new front rotors today from BMA (probably brembos, unless someone can convince me otherwise)

I put on a new set of pads in the fall, and I'm sure they still have lots of life in them, but I'm sure they've formed a comfort fit with the old rotors...

I don't want to put the old pads to new rotors and cause the new rotors to get grooved early on...


So do I spend the extra 50-60 bucks and just buy new pads too?? I'd rather spend as little as possible, and don't want to take the old pads off before their used up.

BMP Designs recommends breaking in new rotors with the to used on them (i.e. use what ya got) and it will enhance the life of the rotor. I've never had a new rotor-new pad combo on any car I've ever owned.
-ashley

Jeff N.
04-18-2005, 10:58 AM
I've never matched them and never had any problems. If the current rotors are really scored, it might take a while for the brake pads to bed to the new rotors. Also, if you were running a very hard pad (ie track pad) and they were scored, might not want to reuse them on new rotors.

I think the official party line is to use new pads with new rotors...

632 Regal
04-18-2005, 11:09 AM
new pads with new rotors, new pads with old rotors not old pads with new rotors. remember to read up on the proper bedding of them.

granit_silber
04-18-2005, 11:53 AM
new pads with new rotors, new pads with old rotors not old pads with new rotors. remember to read up on the proper bedding of them.

"If possible, new discs should be bedded with used pads of the same compound that will be used going forward."

Full Article:
http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

-ashley

Rory535i
04-18-2005, 11:57 AM
"If possible, new discs should be bedded with used pads of the same compound that will be used going forward."

Full Article:
http://www.stoptech.com/whitepapers/warped_rotors_myth.htm

-ashley

that's a first for me. I was always told to put new pads in when getting new rotors.

PhilipJCaputo
04-18-2005, 12:00 PM
I'm actually looking forward to bedding the new rotors!!! I bedded the pads/rotors on my fiance's Jetta last weekend.... after about the 4-5th fast 60-10 stop, I check the rearview mirror and there was a trail of smoke right behind the car!

it was actually kind of fun! I mean when do you really get to do something like that to your car on purpose?

PhilipJCaputo
04-18-2005, 12:01 PM
that's a first for me. I was always told to put new pads in when getting new rotors.

this is almost becoming "blue antifreeze or not"

Hector
04-18-2005, 12:17 PM
just have the rotors turned by a machine shop and you'd be good to go. They check if it can be turned or not. I went through this exercise on my other car but purchased a new set of raybestos pads. I paid $7.50/rotor plus disposal fee. Getting rid of ridges in the rotors makes a huge difference when braking--feels very smooth...no pulsating feel. Since the rotors had been machined, I decided to go with the raybestos pads cuz they are gentler on the rotors as per Bill R's brake post from a while back. I didn't want to get a pad that'd be harsh on the thinner/machined rotors.

Bellicose Right Winger
04-18-2005, 12:24 PM
I'm curious why you are changing them now? If rotors were above "minimum thickness" when you put pads on in the fall then they are good until this set of pads wears out, even if rotor goes below minimum thickness in the process.

How many miles are on the pads? I've reused pads on new rotors without any issues. This is a judgement call you'll have to make after you look at condition of pads. I've also removed the high spots by rubbing pads over a sheet of 60 grit sand paper placed on a sturdy, flat surface. They end up just as flat as new pads. Don't breathe the dust and don't try this if your pads contain asbestos.

Paul Shovestul








I'm thinking about ordering new front rotors today from BMA (probably brembos, unless someone can convince me otherwise)

I put on a new set of pads in the fall, and I'm sure they still have lots of life in them, but I'm sure they've formed a comfort fit with the old rotors...

I don't want to put the old pads to new rotors and cause the new rotors to get grooved early on...


So do I spend the extra 50-60 bucks and just buy new pads too?? I'd rather spend as little as possible, and don't want to take the old pads off before their used up.

PhilipJCaputo
04-18-2005, 12:26 PM
I put on raybestos in the late summer.... they are great! quiet, verry little dust.... but my rotors are beyond repair.... I don't know what size the lip is.. but I'm pretty confident that the lip is more than 1/8th of an inch... it was a pretty significant lip when I put the pads on 20k miles ago, so I'm sure its even worse now.

DaCan23
04-18-2005, 01:07 PM
You've gone 20k miles since last summer? If everything works fine then wait for next pad replacement to do rotors.... IMHO turning rotors is never a good idea unless you drive a $500 car and dont wanna pay $100 for new rotors, especially if you DIY work. But you probably wouldnt want to put on new rotors w/ pads 20k miles into them.

PhilipJCaputo
04-18-2005, 01:21 PM
You've gone 20k miles since last summer? Bought the car in mid june with 111k on the clock, 4000+ mile road trip through north & south dakota, wyoming, colorado, then back to ohio. Plus a couple of trips to kansas city area and back (10 hours each way), and a few more trips to chicago land area (9 hours round trip)... plus its my daily driver, and for a while it was a 30 min trip to the fiance's house... needless to say the miles added up pretty quick this year!


If everything works fine then wait for next pad replacement to do rotors.... I'm getting a good amount of wheel shake when using the brakes, and I know its just messing my already messed up steering components


IMHO turning rotors is never a good idea unless you drive a $500 car and dont wanna pay $100 for new rotors, especially if you DIY work. But you probably wouldnt want to put on new rotors w/ pads 20k miles into them. I think I'll just buy new pads and rotors.... then depending on the life left in these old pads, they can be my backup!

ryan roopnarine
04-18-2005, 01:24 PM
Bought the car in mid june with 111k on the clock, 4000+ mile road trip through north & south dakota, wyoming, colorado, then back to ohio. Plus a couple of trips to kansas city area and back (10 hours each way), and a few more trips to chicago land area (9 hours round trip)... plus its my daily driver, and for a while it was a 30 min trip to the fiance's house... needless to say the miles added up pretty quick this year!

I'm getting a good amount of wheel shake when using the brakes, and I know its just messing my already messed up steering components

I think I'll just buy new pads and rotors.... then depending on the life left in these old pads, they can be my backup!



haw haw haw.....my unloved, abused (by moi) e34 has done about 30k in 8 months..... one trip to canada and back (2800 mi, 9 520 mile trips which seem to happen every month and a half)

i've never driven anything that far in that long, and things like brakes which usually last longer are coming up, which is bizarre to me.

Hector
04-18-2005, 02:01 PM
you have a brain the size of a pea, then power on dude. There is nothing wrong by turning rotors if the shop does a good job and there is a lot of material left on the them. It's nothing to it, and you can hardly screw it up as a DIYer. It's an easy job. Turning rotors for cheap car, give me a friggin break...



You've gone 20k miles since last summer? If everything works fine then wait for next pad replacement to do rotors.... IMHO turning rotors is never a good idea unless you drive a $500 car and dont wanna pay $100 for new rotors, especially if you DIY work. But you probably wouldnt want to put on new rotors w/ pads 20k miles into them.

Kalevera
04-18-2005, 02:53 PM
I might be wrong...but I'm pretty certain that it's not a good idea to bed new brakes this way unless you've got to track the car the next day. You're supposed to be gentle on them for a few hundred miles -- no harsh stops.

DaCan23
04-18-2005, 03:02 PM
Whoa Whoa Hector.... You obviously misread my post, if someone does there own work, IE only cost is parts then why bother turning rotors.. when the cost to replace is only $60+ a set. If your paying someone to do the work then cost can be a issue but your still paying labor. My father is a Master Mechanic and would never ever ever turn rotors on any car worth a while... Sorry dude some of us are just raised right... If your gonna be cheap then...... but most of us here take very good care of our cars and are too anal to turn rotors..


you have a brain the size of a pea, then power on dude. There is nothing wrong by turning rotors if the shop does a good job and there is a lot of material left on the them. It's nothing to it, and you can hardly screw it up as a DIYer. It's an easy job. Turning rotors for cheap car, give me a friggin break...

Kent Carlson
04-18-2005, 03:03 PM
that's a first for me. I was always told to put new pads in when getting new rotors.

Hey Rory,

Just trying to figure out what your caption in the sig is supposed to say. It isnt making sense to me.

Kent

JonE
04-18-2005, 03:13 PM
I had the rotors turned on my E30 awhile back with no ill effects, needed new pads, wear indicator and all was well. Even the lathe jockey at the auto parts store mentioned that the rotors would "probably" warp, even though they were within spec for thickness and runout was fine. Like Hector mentioned, it was worth it for me and I'll probably need new rotors next time. Stock rotors are not all that expensive, so, to each his own.

PhilipJCaputo
04-18-2005, 07:48 PM
somehow I missed your post....

I'm changing rotors becase i'm starting to get a good amount of shaking when I brake... I didn't change them then becuase I wanted to hold out until the last moment.

I may smooth the pads out like you suggested.... I was just worried that the face of the pad would become un-parallel with its metal backing....

most of the miles I've driven over the last 9 months have easily been 70% highway, so not much stopping, I'm not exactly sure how much life is left in the pads, but I'm sure it is quite a bit.


do Raybestos pads have asbestos?? (you would think they do from their name)




I'm curious why you are changing them now? If rotors were above "minimum thickness" when you put pads on in the fall then they are good until this set of pads wears out, even if rotor goes below minimum thickness in the process.

How many miles are on the pads? I've reused pads on new rotors without any issues. This is a judgement call you'll have to make after you look at condition of pads. I've also removed the high spots by rubbing pads over a sheet of 60 grit sand paper placed on a sturdy, flat surface. They end up just as flat as new pads. Don't breathe the dust and don't try this if your pads contain asbestos.

Paul Shovestul

Bellicose Right Winger
04-18-2005, 08:09 PM
Why bother? I get rotors turned for $10 each. Best delivered price for my E34 rotors is closer to $120 from Zygmunt. Turning rotors is factory approved and is perfect for the DIYer.

Professional mechanics have a much bigger incentive to use new. Why tie up the lift for half a day waiting for rotors to be sent out and returned, when the customer will foot the bill for new?

Raised right? I have a different word for spending money unnecessarily and it isn't smart or anal.

Paul Shovestul





Whoa Whoa Hector.... You obviously misread my post, if someone does there own work, IE only cost is parts then why bother turning rotors.. when the cost to replace is only $60+ a set. If your paying someone to do the work then cost can be a issue but your still paying labor. My father is a Master Mechanic and would never ever ever turn rotors on any car worth a while... Sorry dude some of us are just raised right... If your gonna be cheap then...... but most of us here take very good care of our cars and are too anal to turn rotors..

Bellicose Right Winger
04-18-2005, 08:35 PM
If you've got braking related vibrations then you need to replace your rotors or get them turned. Sounds like you're doing this yourself so you have a few options. Check the yellow pages or ask your local parts supplier who turns rotors in the area. Give them a call, ask for a price and take your rotors over. They'll check the thickness and tell you if they can be turned or not. On the other hand if you've got access to a micrometer you can measure the rotor and save yourself a trip. Minimum thickness for 525/530/535 is 20.4mm (.803").

I doubt you'll have to remove enough material from the pads to affect the parallelism.

I agree you've probably got a lot of life left in the pads.

I don't think Raybestos has used asbestos in years. PBR Deluxes were using asbestos until 2-3 years ago.

Paul Shovestul






I'm changing rotors becase i'm starting to get a good amount of shaking when I brake... I didn't change them then becuase I wanted to hold out until the last moment.

I may smooth the pads out like you suggested.... I was just worried that the face of the pad would become un-parallel with its metal backing....

most of the miles I've driven over the last 9 months have easily been 70% highway, so not much stopping, I'm not exactly sure how much life is left in the pads, but I'm sure it is quite a bit.


do Raybestos pads have asbestos?? (you would think they do from their name)

PhilipJCaputo
04-18-2005, 10:12 PM
I think turning is a good option.... I would turn my rotors 4 times over on my honda... but those rotors don't have quite the lip that mine do.... I'll post some pix when I do the work.

but I do REALLY like the idea of sanding the pads down a little to smooth them out.... I was thinking that it would be possible, all I needed was one person to solidify the idea, and give me a starting point! So I'm certainly going to reuse the pads then!




Why bother? I get rotors turned for $10 each. Best delivered price for my E34 rotors is closer to $120 from Zygmunt. Turning rotors is factory approved and is perfect for the DIYer.

Professional mechanics have a much bigger incentive to use new. Why tie up the lift for half a day waiting for rotors to be sent out and returned, when the customer will foot the bill for new?

Raised right? I have a different word for spending money unnecessarily and it isn't smart or anal.

Paul Shovestul

Rory535i
04-18-2005, 11:18 PM
Hey Rory,

Just trying to figure out what your caption in the sig is supposed to say. It isnt making sense to me.

Kent

lol, it's german. It says "drive it like you stole it!"

Kent Carlson
04-19-2005, 09:40 AM
lol, it's german. It says "drive it like you stole it!"

Now I can see it a bit. I am assuming you dont speak much German. So, I might sound like an a$$ when I ask who in world translated that line for you?

Maybe it was an online translator? Anyways, not even close. Funny though. :D :D

Stahl is steel, as in the metal.

Stehlen is to steal.

Funny thing is, my english spelling is so terrible I had to use spellchecker to make sure I got the "ee" and "ea" in the right words.

If you like, I can give you a legit translation.

Rory535i
04-19-2005, 09:52 AM
i dont speak a word of german. got it from a translator for a bit of fun! (usless thing.....) lol

Kent Carlson
04-19-2005, 10:52 AM
i dont speak a word of german. got it from a translator for a bit of fun! (usless thing.....) lol

This is actually an interesting challenge. Translated directly, it looses a lot of the meaning and disreguard for the cars well being.

I think i will kick it around a little with some translators I work with. Off the top of my head, the German "Fahr wie der Teufel" (Drive like the devil) gets prety close to the implied meaning but looses the stolen analagy.

which translator did you use? It realy is terrible. :D