new brake discs?

qwertyjjj · Post by **qwertyjjj** » 30 Mar 2016, 04:56

At what point or mileage would new brake discs be needed?
Garage has quoted for new pads and new discs.
Car is a v70 2004 about 108,000km.

Post by **abscate** » 30 Mar 2016, 05:17

It really depends much more on driving habits (the convolution of traffic and aggressive factor) than miles.

60k in stop and go city traffic will likely need new rotors. Volvo will have a spec on minimum thickness,

A lot of garages will no longer turn rotors since they make more selling you new ones.

The only way to really keep this stuff on budget is to DIY, measure rotors, take them to a shop for turning checking tolerances....

For my 2005 it's 28mm new, 25mm wear limit

qwertyjjj · Post by **qwertyjjj** » 30 Mar 2016, 05:19

Is 108,000 reasonable for a change?
How can I measure them without taking wheels off?

Presumably front pads and discs wear before rear so is there any sense in changing front and rear at the same time?

Post by **abscate** » 30 Mar 2016, 05:23

You need to take the wheels of to get most calipers around the rotor in my experience but I haven't tried it on my 2005.

On edit - calipers here mean measurement calipers, not brake calipers

108kkm is definitely reasonable,a bit on the short side

If you snap a pic and can see the wear pattern on the rotor where the pads touch, it's likely you are near the 3mm wear limit

MarcM · Post by **MarcM** » 30 Mar 2016, 05:49

Wasn't going to post, but it got the better of me.
RockAuto.com (and most retail parts stores) have what's called a brake/rotor kit. Comes with pads and rotors. I generally get the pad/rotor kit and get the caliper "unloaded" (just the caliper). Looks like (CAD$) $100 - $200 for both sides front. You will have to measure the rotor diameter to get the correct one though.
Stores do offer loaded caliper kits (calipers/pads), but I have certain brand preference for the pads. Rotor not included.
http://www.rockauto.com/en/catalog/volvo,2004,v70
Currently I'm running O'Reilly's ceramic pads. Needed a cheap "temporary" set and these were the same price as semi-metallic. I think I paid $30 (USD) for the front rotors. It's not my intended setup of drilled or drilled & slotted w/ceramic but they've treated me well for 5k+ miles.

You can also "bring your own steak to the steakhouse". A lot of independent shops will let you bring your own parts, you just pay labor / shop supplies (caliper grease, brake cleaner to get the protective film off rotors) if you're not comfortable doing your own work. The hesitance is because a lot of their $ is made in parts markup, kind of what keeps them in business. E.g. I called an independent for a price to install my waterpump / timing belt kit and using my antifreeze (I carry a full flush in the trunk of 50/50 Pentosin NF). $350 labor.

Post by **oragex** » 30 Mar 2016, 06:34

First thing to remember, replacing brakes is the favorite job a mechanic will 'recommend'. In other words, few people know how to check their brakes for wear, and garages will often times replace them when still good.
I'd suggest having a look or taking a picture and uploading it here. There is no exact mileage where brakes need to be replaced on a specific car. It all depends on how the car is driven. I can drive a car for 100K with the same pads and discs in city driving. Another driver may need new pads after 15K miles.
The pads are easy to inspect for wear by looking through the wheel spikes. Same goes for the discs by looking how deep they wore comparing the center portion with the inner side portion (where the pads don't touch). In my opinion, if the discs are still good, there is no need to replace them just because new pads are installed.

Post by **abscate** » 30 Mar 2016, 08:24

Safety note - don't touch the rotor until your car has sat cold for many hours, or else you will do the same neural speed experiment I did on my bug - comparing the speed of sound (flesh on fingers sizzling) to the pain transmission speed up the brachial nerve to the pain receptor, and the brain translation to "Dont do that again"

Post by **oragex** » 30 Mar 2016, 10:23

abscate wrote:Safety note - don't touch the rotor until your car has sat cold for many hours, or else you will do the same neural speed experiment I did on my bug - comparing the speed of sound (flesh on fingers sizzling) to the pain transmission speed up the brachial nerve to the pain receptor, and the brain translation to "Dont do that again"

I just did so last week, it hurt

qwertyjjj · Post by **qwertyjjj** » 30 Mar 2016, 16:06

I'll go grab a pic in a moment.
Garage has quoted me :
Set Front pads CAD$106
Set Front discs CAD$240
Oiling front discs CAD$10

Set back pads CAD$88
Set back discs CAD$211
oiling back discs CAD$10

Then it's $80 per hour labour

Post by **oragex** » 30 Mar 2016, 18:34

The quote is parts only? Is so, I'd forget them, it's very expensive and they will probably put cheap parts.

Never heard about oiling the discs. Perhaps they meant the caliper pins, which should not be greased on a Volvo.

You can buy the parts online. I am pleased with the Akebono pads, brembo disks are good, others may suggest other options.