Do I really need new pads with new discs?

Daftasabrush · 09-29-2020, 04:38 PM

Got Porterfield R4-S front and rear currently, need new front discs so got a pair of Textars. The front pads have 11mm left on them which, to me, seems plenty. They're 2 years old but still seem fine.

Why should I change the perfectly fine pads with the new discs?

Billfitz · 09-29-2020, 05:05 PM

The bulk of the cost of a rotor job is labor. The added labor cost of new pads versus using the old pads should be zero.

Daftasabrush · 09-30-2020, 05:41 AM

I do it myself so there's no labour costs, I'm just wanting to understand why I should replace them when they don't need it.

Billfitz · 09-30-2020, 07:09 AM

That being the case I wouldn't.

brigade24 · 09-30-2020, 02:32 PM

Quote:

Originally Posted by Daftasabrush

Got Porterfield R4-S front and rear currently, need new front discs so got a pair of Textars. The front pads have 11mm left on them which, to me, seems plenty. They're 2 years old but still seem fine.

Why should I change the perfectly fine pads with the new discs?

you dont have too change the pads. particularly if you plan on using a new set of R4S pads again on that new rotor once the pads you have now wear out. just make sure to clean the rotors good and bed the pads in properly and you're good to go.

Daftasabrush · 09-30-2020, 04:05 PM

Thanks, I just like the pads I have and don't see anything wrong with them. I was hoping to get two sets of pads out of a set of discs but that's not the case. I wasn't planning on using the same pads again, they're difficult to get here in the UK but if I don't have to think about new pads then I won't!

Skyhigh · 10-02-2020, 06:54 AM

Pads are always to be replaced when fitting new discs! It is not because of thickness, but because of wear pattern.

https://www.clickmechanic.com/blog/s...y-brake-discs/

Besides that, the cost of pads is usually small in comparison to the price of discs (and labour). And there is no additional labour for replacing the pads either, once you go for new discs.

340iGUY · 10-02-2020, 08:37 AM

I would re-use the old pads but sand them down before using on new rotors.

BBri89 · 10-02-2020, 08:40 AM

I'd echo Skyhigh there, it's not just because pads are normally worn out when its time to do the discs, but because of the shape of the pad surface after they are worn.

Worn pads will match the disc surface, but may not make maximum contact with new disc surface.

If the pads don't need replacing, can the discs be kept a bit longer until the pads are a little more worn?
If discs have to be replaced, I'd strongly advise doing the pads too.

Daftasabrush · 10-10-2020, 11:05 AM

Hmm, I'd not heard that one before. The pads cost nearly twice what the discs cost me so was hoping to keep them

weehe126 · 10-10-2020, 11:45 AM

If the old pads wore evenly then you can reuse them. If they have a lip or weird wear I'd replace them.

Skyhigh · 10-10-2020, 12:17 PM

A used pad is never 100% even, even if it appears so.

BWbimmer · 10-10-2020, 12:29 PM

Quote:

Originally Posted by Daftasabrush

Hmm, I'd not heard that one before. The pads cost nearly twice what the discs cost me so was hoping to keep them

I think you should do a bit more research because the pads a definetly only half of the price of one disk. Brembo pads shouldn't be more than 50Pounds p.e.

Daftasabrush · 10-10-2020, 12:40 PM

Quote:

Originally Posted by BWbimmer

I think you should do a bit more research because the pads a definetly only half of the price of one disk. Brembo pads shouldn't be more than 50Pounds p.e.

The Porterfields I have aren't cheap, nor are the other options I'm looking at. I got a bargain on the Textar discs at £100 a corner

zinner · 10-11-2020, 10:04 AM

If the old rotors caused uneven wear on the pads then I would replace. I would inspect the pads and make the call. I don't know that specific pad but pads can be aggressive enough to score the rotor surface if it's uneven and you might be back to square one in a few miles down the road. Trump 2020

09-29-2020, 04:38 PM	#1
Daftasabrush Fool 1857 Rep 3,542 Posts Drives: F31 340i Join Date: Jul 2014 Location: England iTrader: (0)	Do I really need new pads with new discs? Got Porterfield R4-S front and rear currently, need new front discs so got a pair of Textars. The front pads have 11mm left on them which, to me, seems plenty. They're 2 years old but still seem fine. Why should I change the perfectly fine pads with the new discs? __________________
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09-29-2020, 05:05 PM	#2
Billfitz Lieutenant General 8243 Rep 16,082 Posts Drives: '15 328iX GT Join Date: Jan 2015 Location: New Hampshire iTrader: (0)	The bulk of the cost of a rotor job is labor. The added labor cost of new pads versus using the old pads should be zero.
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09-30-2020, 05:41 AM	#3
Daftasabrush Fool 1857 Rep 3,542 Posts Drives: F31 340i Join Date: Jul 2014 Location: England iTrader: (0)	I do it myself so there's no labour costs, I'm just wanting to understand why I should replace them when they don't need it. __________________
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09-30-2020, 07:09 AM	#4
Billfitz Lieutenant General 8243 Rep 16,082 Posts Drives: '15 328iX GT Join Date: Jan 2015 Location: New Hampshire iTrader: (0)	That being the case I wouldn't.
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09-30-2020, 04:05 PM	#6
Daftasabrush Fool 1857 Rep 3,542 Posts Drives: F31 340i Join Date: Jul 2014 Location: England iTrader: (0)	Thanks, I just like the pads I have and don't see anything wrong with them. I was hoping to get two sets of pads out of a set of discs but that's not the case. I wasn't planning on using the same pads again, they're difficult to get here in the UK but if I don't have to think about new pads then I won't! __________________
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10-02-2020, 06:54 AM	#7
Skyhigh Brigadier General 1887 Rep 3,873 Posts Drives: BMW F36 Join Date: Apr 2018 Location: Europe iTrader: (0)	Pads are always to be replaced when fitting new discs! It is not because of thickness, but because of wear pattern. https://www.clickmechanic.com/blog/s...y-brake-discs/ Besides that, the cost of pads is usually small in comparison to the price of discs (and labour). And there is no additional labour for replacing the pads either, once you go for new discs. __________________ "Large increases in cost with questionable increases in performance can be tolerated only in cars and women."
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10-02-2020, 08:37 AM	#8
340iGUY Enlisted Member 15 Rep 40 Posts Drives: 340i manual Join Date: Sep 2020 Location: US iTrader: (0)	I would re-use the old pads but sand them down before using on new rotors.
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10-02-2020, 08:40 AM	#9
BBri89 Captain 516 Rep 749 Posts Drives: F31 320d xDrive M Sport Join Date: Jul 2020 Location: West Sussex, UK iTrader: (0) Garage List 2015 BMW 320d xDriv ... [0.00]	I'd echo Skyhigh there, it's not just because pads are normally worn out when its time to do the discs, but because of the shape of the pad surface after they are worn. Worn pads will match the disc surface, but may not make maximum contact with new disc surface. If the pads don't need replacing, can the discs be kept a bit longer until the pads are a little more worn? If discs have to be replaced, I'd strongly advise doing the pads too. __________________ 2015 F31 320d xDrive M Sport (Plus pack) *My progress thread*
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10-10-2020, 11:05 AM	#10
Daftasabrush Fool 1857 Rep 3,542 Posts Drives: F31 340i Join Date: Jul 2014 Location: England iTrader: (0)	Hmm, I'd not heard that one before. The pads cost nearly twice what the discs cost me so was hoping to keep them __________________
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10-10-2020, 11:45 AM	#11
weehe126 Brigadier General 1161 Rep 3,189 Posts Drives: 2017 340i Join Date: Apr 2014 Location: San Antonio iTrader: (2)	If the old pads wore evenly then you can reuse them. If they have a lip or weird wear I'd replace them.
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10-10-2020, 12:17 PM	#12
Skyhigh Brigadier General 1887 Rep 3,873 Posts Drives: BMW F36 Join Date: Apr 2018 Location: Europe iTrader: (0)	A used pad is never 100% even, even if it appears so. __________________ "Large increases in cost with questionable increases in performance can be tolerated only in cars and women."
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10-11-2020, 10:04 AM	#15
zinner Major 559 Rep 1,127 Posts Drives: `17 X5 35d/`15 335i/`18 M550IX Join Date: Oct 2014 Location: Raleigh, NC iTrader: (0)	If the old rotors caused uneven wear on the pads then I would replace. I would inspect the pads and make the call. I don't know that specific pad but pads can be aggressive enough to score the rotor surface if it's uneven and you might be back to square one in a few miles down the road. Trump 2020
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