Brake pad change - turn rotors?

[Slickone]

Time to replace the OE front pads on my 2000 Nissan Frontier (47K). Doing the work myself. I know shops always turn the rotors, perhaps just to CYA, or for more money. Just wondering if I really need to do that. I have no squealing or pedal pulsation. FYI, I'll be installing Raybestos Professional Grade ceramic.

 

[SparkyJJO]

If your pedal doesn't pulse and the rotors are smooth on the surface then the rotors probably don't need turned.

 

[mwmorph]

I always turn them if I can, depends on the condition of the rotors and how the pads seated though.

 

[GoatMonkey]

I think brake shops turn the rotors more than they really need to just so you have to come back sooner.

 

[thomsbrain]

My understanding is that rotors only need to be turned if they are warped. Otherwise, you're just giving up rotor thickness for no reason, and increasing the chances that they WILL warp down the road. I'd say if you aren't getting pulsing and the thickness is ok, just leave them and do a pad slap.

 

[DougK62]

I wouldn't turn them. You may get poorer braking for a bit as the new pads wear to the grooves already in the rotors, but it won't last long and you'll be fine.

 

[Slickone]

Cool. Thanks guys. I won't turn them then, and I'll feel better about my decision now. 🙂

 

[jagec]

If you really want MAXIMUM braking performance, you should turn the rotors, and bed the new pads+rotors in properly. But no one does that, not even brake shops...so if you're not going to bed them in, and the current rotors are true, just slap on the new pads.

 

[Zenmervolt]

Originally posted by: jagec
If you really want MAXIMUM braking performance, you should turn the rotors, and bed the new pads+rotors in properly. But no one does that, not even brake shops...so if you're not going to bed them in, and the current rotors are true, just slap on the new pads.

Well, you could do what I'm going to do when the S70 needs new pads and just buy new aftermarket rotors and high-performance pads... 😉 Might be overkill though. 😛

ZV

 

[flamingelephant]

if you put on new pads, resurfacing the rotors will increase performance and how long they last, and is should be cheap to do as well... there is really no excuse

 

[Jeff7]

What's involved in turning rotors? I have fairly new rotors (less than a year old), and they pulse a bit when braking. I've heard that shops may torque the hell out of rotors, when they're supposed to use a torque wrench, to avoid warping.

 

[jagec]

Originally posted by: Jeff7
What's involved in turning rotors? I have fairly new rotors (less than a year old), and they pulse a bit when braking. I've heard that shops may torque the hell out of rotors, when they're supposed to use a torque wrench, to avoid warping.

They put each rotor on a lathe, and carve a new, clean, flat surface on each side.

Shops are very bad about using torque wrenches on wheels, and that can indeed warp the rotors in some cases.

 

[LennyZ]

Turning rotors removes mass and makes warping even more likely.
I do new rotors on every brake job.

 

[cardiac]

If you don't turn them, at least take some emery cloth to the rotors and knock the glaze off. They will be a little shiny from the old pads; just knock the shine down....

Bob

 

[zerocool84]

Originally posted by: cardiac
If you don't turn them, at least take some emery cloth to the rotors and knock the glaze off. They will be a little shiny from the old pads; just knock the shine down....

Bob

yep you want to atleast get rid of the glaze that is left from the old pads since when you get new pads, if you bed them in properly they will leave a new glaze on them and that is what really helps with the braking

 

[Slickone]

Originally posted by: flamingelephant
if you put on new pads, resurfacing the rotors will increase performance and how long they last,

Explain?

and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

 

[Zenmervolt]

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

 

[cardiac]

Originally posted by: Zenmervolt

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

Not a car....but if I remember right, my 1976 Dodge Ramcharger had the rotors with the hub/bearing all in one unit. Was full-time 4WD... What a beast...

But, I am old, that was over 25 years ago, and my memory ain't what it used to be 😉

Bob

 

[Slickone]

Originally posted by: Zenmervolt

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

It's the truck listed in the OP. Not odd at all. They used to all be that way (I did quite a few back in the day). Aren't all front rotors on RWD's still like that?
Like this.

 

[Pacfanweb]

Originally posted by: flamingelephant
if you put on new pads, resurfacing the rotors will increase performance and how long they last,

Machining rotors will do nothing of the sort. Only reason to machine is if the rotors are either really grooved, or warped.

The fact of the matter is, new pads will stop you better initially if you DON'T turn the rotors.

If you've done thousands of brake jobs and test-driven the cars afterward, you'd know this.

It takes awhile for the pads to seat to freshly-turned rotors, and they don't stop worth a crap at first. They're really sort of dangerous.

A good way to break the pads in quickly is to simply ride around the block with your foot lightly on the brake. You don't want to scald them, but you want to smell the brakes a little when you get back.
Let it cool, and it'll stop like a champ. Works for either a pad-slap or if you machine the rotors.

 

[Pacfanweb]

Originally posted by: Zenmervolt

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

Craploads of older cars are like this. In fact, pretty much anything built before 1995 that isn't front wheel drive is.
I know all Ford trucks from 96 and down have bearings. From 97 and up they have floating rotors. Chevy is probably the same, just don't know which year they started with floating rotors.
Nothing new that I know of, outside of heavy-duty trucks has bearings, though.

 

[Pacfanweb]

Originally posted by: Slickone

Originally posted by: Zenmervolt

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

It's the truck listed in the OP. Not odd at all. They used to all be that way (I did quite a few back in the day). Aren't all front rotors on RWD's still like that?

Nope, not anymore.

 

[jagec]

Originally posted by: Pacfanweb

Originally posted by: flamingelephant
if you put on new pads, resurfacing the rotors will increase performance and how long they last,

Machining rotors will do nothing of the sort. Only reason to machine is if the rotors are either really grooved, or warped.

The fact of the matter is, new pads will stop you better initially if you DON'T turn the rotors.

If you've done thousands of brake jobs and test-driven the cars afterward, you'd know this.

It takes awhile for the pads to seat to freshly-turned rotors, and they don't stop worth a crap at first. They're really sort of dangerous.

A good way to break the pads in quickly is to simply ride around the block with your foot lightly on the brake. You don't want to scald them, but you want to smell the brakes a little when you get back.
Let it cool, and it'll stop like a champ. Works for either a pad-slap or if you machine the rotors.

I think he means that machining the rotors, then properly bedding in the pads.

I usually do an actual procedure, similar but not exactly like this one:
Step 1:
Decelerate from 35mph to 5mph - using moderate brake presure (70-75%)
Do not come to a complete stop. Gently re-accelerate to 40mph.
Repeat this process 4-6 times.

Step 2:
Decelerate from 45mph to 0mph - using more brake pressure (85%)
Do not lock the brakes. Do not STAY stopped with your foot on the brake pedal - allow the car to roll slightly. Gently re-accelerate to 45mph.
Repeat this process 3 times.

Step 3:
Drive a short distance - allowing the brakes to cool.
Park the vehicle, and allow the brake system to fully cool to ambient (outside) temperatures (15-30 minutes). While stopped, do not apply the parking brake or keep your foot on the brake pedal for extended periods of time.

 

[Zenmervolt]

Originally posted by: Pacfanweb

Originally posted by: Zenmervolt

Originally posted by: Slickone

Originally posted by: flamingelephant
and is should be cheap to do as well... there is really no excuse

Sure there is. On mine, I'd have to remove the bearings to get the rotors off, hopefully have an extra vehicle, and take them somewhere to get turned.

What car? That's a very odd setup. I can't think of a car off the top of my head that has the rotors cast integrally with the hub.

ZV

Craploads of older cars are like this. In fact, pretty much anything built before 1995 that isn't front wheel drive is.
I know all Ford trucks from 96 and down have bearings. From 97 and up they have floating rotors. Chevy is probably the same, just don't know which year they started with floating rotors.
Nothing new that I know of, outside of heavy-duty trucks has bearings, though.

Interesting. That's what I get for working on euro cars. The rotors on my old Porsches are held on largely by the lug bolts, just a couple of locating screws to keep them on the hubs when you take the wheels off. Even the 1970's Fiat Spider I did the brakes on was set up that way. Serves me right for not expanding my range of cars that I play with. 😛

That'll teach me not to extrapolate so much in the future. 🙂

ZV