Brake Rotor Question

[The Critic]

I have a '96 Saturn SL2 with 141k on it.

At about 88,000 miles, the original front pads were getting low so a mechanic resurfaced the front rotors and installed a new set of Duralast Gold ceramic pads.

After 53,000 miles, the pads still have about 1/2 left. However, the rotors have a huge lip on them. While the surface isn't rough or grooved, it is apparent that the rotors have some serious wear on them.

I know for a fact that when the front pads were replaced, the rotors still had enough meat on them or else they would not have been returned to service. So theoretically, the brake system is safe and suitable for continued use, right?

So, the question is: if the pads are still fine but the rotors appear heavily worn (even though the rotors were perfectly serviceable when the pads were installed), does the brake system need attention?

Thanks!

 

[JustinH]

The only way to tell how much surface is left on the rotor is to get the book of specs for that saturn, and measure with a rotor micrometer.

Sometimes they stamp this measurement on the rotor itself.

You can measure the runout of the rotor also with a dial indicator.

If you don't already have these tools, then you mine as well just go by feel, and replace the rotors.

Rotors for a saturn are going to be dirt cheap.

 

[oilboy123]

If they have a lip on them and have been turned it would be a good idea to check the thickness and or replace them. Brakes are not the parts you want to assume things with........
If they were turned and were 0.020 above discard thickness they could 0.020 below discard now. But you would not know that without checking them. They might be OK but they might not.

Do you feel lucky Punk? Well do you? Sorry could not resist.

I try to measure rotors/drums after turning and record the specs for reference.

 

[The Critic]

Originally Posted By: oilboy123
If they have a lip on them and have been turned it would be a good idea to check the thickness and or replace them. Brakes are not the parts you want to assume things with........
If they were turned and were 0.020 above discard thickness they could 0.020 below discard now. But you would not know that without checking them. They might be OK but they might not.

Do you feel lucky Punk? Well do you? Sorry could not resist.

I try to measure rotors/drums after turning and record the specs for reference.


Oh, I know they are well below the minimum thickness. Pep Boys measured them during a brake inspection visit at 115k and they were already below minimum then, so I'm sure they are well below now.

But the question really is, if they are below minimum now but they were above minimum when the pads were installed, do the rotors still need to be replaced?

 

[willix]

If the rotor is still in tolerance & it turns smooth without pulsating, Run them. Rotors are about $20 new, If DIY R&R the fronts, the rear axle only bears 30 to 40% of the braking duty and wouldn't be as concerned if in tolerance.

 

[The Critic]

Originally Posted By: willix
If the rotor is still in tolerance & it turns smooth without pulsating, Run them. Rotors are about $20 new, If DIY R&R the fronts, the rear axle only bears 30 to 40% of the braking duty and wouldn't be as concerned if in tolerance.

The reason I'm asking this question is because I just scored a cheap set of HPS pads that I want to install. I was originally going to wait until these pads wear out, but if my rotors need to be replaced anyway, then I may as well do the job now.

Besides, braking performance is rather mediocre with the current setup.

 

[chad8]

Originally Posted By: The Critic
Originally Posted By: oilboy123
If they have a lip on them and have been turned it would be a good idea to check the thickness and or replace them. Brakes are not the parts you want to assume things with........
If they were turned and were 0.020 above discard thickness they could 0.020 below discard now. But you would not know that without checking them. They might be OK but they might not.

Do you feel lucky Punk? Well do you? Sorry could not resist.

I try to measure rotors/drums after turning and record the specs for reference.


Oh, I know they are well below the minimum thickness. Pep Boys measured them during a brake inspection visit at 115k and they were already below minimum then, so I'm sure they are well below now.

But the question really is, if they are below minimum now but they were above minimum when the pads were installed, do the rotors still need to be replaced?


It depends how lucky you feel. Would I drive on them. Probably. Do you stand a chance of cracking, warping, or exploding a rotor. sure.
I would do this. shop intently for a sale on a new set of rotors and pads via either ebay , craigslist or local sale and buy them in the next couple weeks to a month. Then any craigslist mechanic or diy can put them on in less than an hour when the weather is good and you don't have to worry about it. Do not let pep boys touch your car. Their mechanics are the Micky d's of car care.
That way ,you can save up money to buy them , and probably get the whole deal done for under $75 like I have done with my corolla's. I have even run used rotors that i bought from the local u-pull junkyard and used pads .I bought a dial caliper from harbor freight for about $5 to measure them first. I think I have a set of these pads on now. you have to know what u are looking for. I found a donor car with new brakes that god totaled. Saturns are cheap to maintain and parts are dirt cheap.
Is it an emergency situation. no . Should you start to think about getting it done. You wouldn't be on here asking if you did not think so. Just be smart and proactive.

 

[Familyguy]

Originally Posted By: The Critic
Originally Posted By: willix
If the rotor is still in tolerance & it turns smooth without pulsating, Run them. Rotors are about $20 new, If DIY R&R the fronts, the rear axle only bears 30 to 40% of the braking duty and wouldn't be as concerned if in tolerance.

The reason I'm asking this question is because I just scored a cheap set of HPS pads that I want to install. I was originally going to wait until these pads wear out, but if my rotors need to be replaced anyway, then I may as well do the job now.

Besides, braking performance is rather mediocre with the current setup.


Rotors are dirt cheap. Based on your description, it sounds like they're below spec. Might as well get it over with now and take comfort in the fact that you'll have substantially better brakes. The HPS pads are nice...a little dusty, but you should experience a noticeable improvement in stopping distance.

Best,

 

[bluestream]

If you want to change the pads, change the rotors as well.

 

[mechtech2]

For light street use, you should be just fine. If there is no pulsation in the pedal, or pad sticking, leave them alone.
Replace the rotors when the pads get too thin.

But what if you subject the car to serious braking? Then things change. Then you want things more perfect.

 

[The_Jeff]

There's a service limit and a discard limit; discard will be thinner. They designed the service limit so you'd still be at or above discard when you next need brakes... more or less.

This doesn't stop an unscrupulous garage from saying, well, in a little bit you'll be at the service limit, better buy rotors now while I have it apart.

Regardless I'd get new rotors. Rockauto seems to be the go-to place even including shipping.

 

[Chris142]

The A-Zone pads on my Jeep have really eaten away at my rotors too. They are way undersized but not warped or shake when using the brakes.

If this makes you feel any better I had this roll into the shop on Friday.

 

[jumpr]

Originally Posted By: Chris142
The A-Zone pads on my Jeep have really eaten away at my rotors too. They are way undersized but not warped or shake when using the brakes.

If this makes you feel any better I had this roll into the shop on Friday.

If that's what the rotor looked like, what kind of condition were the pads in? What caused the customer to bring the vehicle in? Were the brakes making some kind of horrible noise?

 

[willix]

That is caused by gross neglect. Its easy to see the caliper was stuck.

 

[benjamming]

Rotors are mfg to the thinnest amount possible. I wonder if the servicing limit allowing you to turn the rotors is made possible by the OEM marketing department. OEM beats the rotor mfg to make the rotors as thin as possible & still get by when new. It goes way downhill from there after turning just once. On top of that, what kind of spec is held by parts stores when turning - very poor. With that said, it's probably pretty obvious my take - new rotors. The question then becomes, do you replace the pads now or wait until they are worn?

 

[The Critic]

Originally Posted By: eljefino
There's a service limit and a discard limit; discard will be thinner. They designed the service limit so you'd still be at or above discard when you next need brakes... more or less.

This doesn't stop an unscrupulous garage from saying, well, in a little bit you'll be at the service limit, better buy rotors now while I have it apart.

Regardless I'd get new rotors. Rockauto seems to be the go-to place even including shipping.

What is the discard limit for these rotors?

According to my database, I only see a new and minimum thickness listed.

Originally Posted By: benjamming
Rotors are mfg to the thinnest amount possible. I wonder if the servicing limit allowing you to turn the rotors is made possible by the OEM marketing department. OEM beats the rotor mfg to make the rotors as thin as possible & still get by when new. It goes way downhill from there after turning just once. On top of that, what kind of spec is held by parts stores when turning - very poor. With that said, it's probably pretty obvious my take - new rotors. The question then becomes, do you replace the pads now or wait until they are worn?


If I wait until the pads wear out, that could easily be another 50,000 miles.

As a side note, I find it interesting how GM says that for brake rotor scoring that is less than 1.5mm deep, there is no need to resurface the brake rotors. Yet, there's only a 1.5mm difference between the new and discard thickness specs for the rotors on a Grand Prix!

http://townhall-talk.edmunds.com/direct/view/[email protected]@

 

[oilboy123]

If I was running rotors that I knew were at or under the limit I would do a brake job.......

If I thought they were thinner than the limit by a ways I would not drive the vehicle until the brakes were done.

 

[HTSS_TR]

Originally Posted By: The Critic

Oh, I know they are well below the minimum thickness. Pep Boys measured them during a brake inspection visit at 115k and they were already below minimum then, so I'm sure they are well below now.

But the question really is, if they are below minimum now but they were above minimum when the pads were installed, do the rotors still need to be replaced?


Originally Posted By: The Critic

The reason I'm asking this question is because I just scored a cheap set of HPS pads that I want to install. I was originally going to wait until these pads wear out, but if my rotors need to be replaced anyway, then I may as well do the job now.

Besides, braking performance is rather mediocre with the current setup.


The highlites telling you should replace both rotors and pads now.

 

[The Critic]

Originally Posted By: HTSS_TR
Originally Posted By: The Critic

Oh, I know they are well below the minimum thickness. Pep Boys measured them during a brake inspection visit at 115k and they were already below minimum then, so I'm sure they are well below now.

But the question really is, if they are below minimum now but they were above minimum when the pads were installed, do the rotors still need to be replaced?


Originally Posted By: The Critic

The reason I'm asking this question is because I just scored a cheap set of HPS pads that I want to install. I was originally going to wait until these pads wear out, but if my rotors need to be replaced anyway, then I may as well do the job now.

Besides, braking performance is rather mediocre with the current setup.


The highlites telling you should replace both rotors and pads now.

Probably...before I die on Highway 17.

I should probably replace my LCA and lower ball joints too.

But my dad says that it's an old car, so I should treat it like an old car and not worry about it. LOL.

 

[mechtech2]

Chris142 - That's a strong candidate for a worn brake awards!
My version is AMG Mercedes brakes at Road America.
When they came in to the pits with both front brakes on fire, an inspection seemed like a good idea.
Worn past the pads, past the backing plate, and was braking on the pistons. At least until the pistons wore so much that the fluid came out and caught fire from the red hot parts.