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Really, how important is it to turn the Rotors when changing the Brake Pads?

Really, How important is it to have the Rotors turned when changing the Brake Pads? If the Rotors are not worn or warped or burnt why spend the extra money? Costs more to have them turned then it does for the Brake Pads.

I don’t know what vehicle your referring to, but, yes, rotor service typically costs more than new pads. I can buy semi-metallic pads for my truck at $25 a set. It will cost me $15-$20 per rotor to turn them. It will cost me $75. per rotor to replace them.

However, turning the rotors ARE important. The rotors develop a wear pattern with the old pads. Just slapping new pads on means they need to conform to the old wear pattern, which takes longer and forces the pads to wear faster. And the odds of bad brake behavior, like chattering, noise, and warpage increase. In my shop, we turn or replace rotors with every brake job to reset the brake wear pattern and greatly reduce the odds of bad brake behavior. We don’t want to have to re-do jobs by cutting corners.

Shops will always machine or replace the old rotors for the reasons cited by Bustedknuckles. They don’t want any returns or dissatisfied customers.

On my own and friends’ vehicles I’ve often just replaced the pads when there was no sign of warpage, scoring or glazing of the rotors and never had a problem.

Eventually the rotors will wear down to a point where their thickness is below spec., then they need to be replaced.

If you do a brake job yourself and just replace the pads here is what happens. The new pads are smooth and the rotors have “grooves” worn in them from previous use. Therefore the new pads will not mate to the new rotors immediately. You will have brakes, but they won’t be very powerful at first. The pads are supposed to be made of “softer” material than the rotors. The pads will eventually wear and assume the same “grooves” as the rotors. How long will this take? That depends on the pads you buy and how deeply the rotors are grooved. Just don’t expect peak braking performance for awhile.

The new pads will also wear out faster as they go through the intial mating process with the rotors. If you want to save some money and change pads yourself, I’d suggest using a “softer” pad and expect to replace the pads more frequently. The softer pads will wear faster, but they won’t wear down the rotors as fast. With softer pads you might be looking at changing pads every 20 to 30K miles and getting 2 or 3 sets of pads worn before you need to get new replacement rotors.

Professional repair shops could be “liable” if they sent customers home with brakes that are “sub par”. Customers would complain that the brakes don’t feel strong. There can be other problems that crop up when you don’t resurface rotors. Many shops are going to just replacing rotors since resurfacing can cause “redo” brake jobs too.

If you know what you are doing and replace the pads correctly a DIY brake job is not too hard. You just need to adjust your driving with the new brakes. If you have to make panic stops, or need to immediately pull a trailer your vehicle might not even be safe to operate and it might be more prudent to go with resurfacing the rotors.

If they are not warped or scored, there is no reason to turn them…CRC makes a spray-on product called “No Squeal” or “Never Squeal” that “burnishes” the rotors the first few stops and prevents squeaking caused by glazed rotors…

I pad slap perpetually. I never have to turn rotors. Now when my daughters drove my cars, they needed cutting, sure.

I’d recommend bleeding the brakes every 2 years. While brake fluid flushing is a new fad, it was probably done by the average consumer due to having a pro bleed them at every brake job. The DIY’r, like myself, never disturbs the hydraulic system …hence I could eventually absorb enough moisture to foul or corrode my ABS system if I had one.

A proper brake job means turning or replacing the rotors. It’s quite possible (and often happens) that when new pads are installed on old rotors the brakes may make noise or shudder. These symptoms may develop then and there or it may crop up in a week, month, or whatever.

The DIYer can certainly throw a set of pads on and not suffer any problems. However, when a shop is doing this job and is expected to stand behind the job then their point of view is different.
As sure as the sun rises every day if a shop installs a set of pads only as per customer request and the customer is made aware of this problem, that same customer will be back ready to sue if the brakes shudder or make noise.

Really, how important is it to fix it right ?
your choice.

My 79 pickup, probably not. ( throw on some pads just to beat around town )
My 06 Escape hybrid better be showroom perfect after repairs.
your choice.

Thanks for all the feedback. I am a DIY’r and am comfortable with the brake jobs i do on my cars but the problem comes when my wife volenteers my services to friends who need brake work but are really tight on money. I like doing the work but am a little frightened of not doing it right. At the same time if i do the job right it will be out of their budget and then no brake work will get done. Bit of a catch 22:)

Be right up front with your disclaimer.
Even with a cash job and no paperwork tell them and show them their choices.
( same with me hanging ceiling fans, doors, installing running boards or a fan belt for friends or family. )

I don’t have a problem with a DIYer doing pads only on their own car or for a neighbor or friend, etc.
The issue is that sometimes the results are less than the expectations and this can lead to some disgruntled people.

I’ve changed pads only on a number of both my cars and family members cars and usually there is no problem. Sometimes there has been so it’s back up a few steps for a re-do.
In a shop setting (dealer or independent) veering from the prescribed method can generate problems for the shop so this potential pitfall is headed off at the start.