New brakes rotors
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If there is a shimmer in the steering wheel, that means it is most likely the front axle.
You may need to check the runout on the front rotors. Ideally it should be zero. Indexing the rotors may help, in other words rotate the rotors on the hubs to minimize runout.
How recently was the job done? Are we talking a few days or thousands of miles?
Any play in the tie rods can do this too. Make sure the mating surfaces of the rotor and hub are clean of rust.
If the vibration develops immediately after the brake job (i.e. During the test drive), the rotors were improperly machined and are defective.
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
Originally Posted By: Chris142
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
Yes, a lot of the literature from the rotor manufacturers warns to check runout at installation and the value of an on-vehicle lathe.
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
Yes, a lot of the literature from the rotor manufacturers warns to check runout at installation and the value of an on-vehicle lathe.
Originally Posted By: Nissan101
It sucks yes
and i find its ridiculous that oem rotors need to be machined. If i had known this would have been the case, i would have just machined my old ones.
They might have needed to be machined. Or, they may have been installed crooked. In once case I saw, the machine retention screws on a Honda front hub had been broken off almost flush. Almost. The rough surface of the nubs was just enough to hold the rotor crooked and cause shimmy to develop.
3000 miles is just long enough for rotors installed crooked to build up brake pad material on the high spots and give that shimmy feeling. Of course, the shop will blame the owner for "warped rotors".
Originally Posted By: Chris142
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
I used to do that.
Now I check parallelism off the vehicle, and runout on the vehicle. The first catches non-flat rotors so I can return them for full refund before I waste time installing them. The second prevents flat&true rotors from being install crooked.
The parallelism check is just 8 more-or-less equidistant measurements with a micrometer around the disc. Your Factory Service manual has the specs, for example the last car I did was < .0015".
Here's a pic of my runout check last week as I installed new rotors on the old Honda Pilot. Again, the runout spec can be found in your FSM. You know, in the parts every shop skips.
It sucks yes
and i find its ridiculous that oem rotors need to be machined. If i had known this would have been the case, i would have just machined my old ones.
They might have needed to be machined. Or, they may have been installed crooked. In once case I saw, the machine retention screws on a Honda front hub had been broken off almost flush. Almost. The rough surface of the nubs was just enough to hold the rotor crooked and cause shimmy to develop.
3000 miles is just long enough for rotors installed crooked to build up brake pad material on the high spots and give that shimmy feeling. Of course, the shop will blame the owner for "warped rotors".
Originally Posted By: Chris142
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
I used to do that.
Now I check parallelism off the vehicle, and runout on the vehicle. The first catches non-flat rotors so I can return them for full refund before I waste time installing them. The second prevents flat&true rotors from being install crooked.
The parallelism check is just 8 more-or-less equidistant measurements with a micrometer around the disc. Your Factory Service manual has the specs, for example the last car I did was < .0015".
Here's a pic of my runout check last week as I installed new rotors on the old Honda Pilot. Again, the runout spec can be found in your FSM. You know, in the parts every shop skips.
Originally Posted By: HangFire
Originally Posted By: Nissan101
It sucks yes
and i find its ridiculous that oem rotors need to be machined. If i had known this would have been the case, i would have just machined my old ones.
They might have needed to be machined. Or, they may have been installed crooked. In once case I saw, the machine retention screws on a Honda front hub had been broken off almost flush. Almost. The rough surface of the nubs was just enough to hold the rotor crooked and cause shimmy to develop.
3000 miles is just long enough for rotors installed crooked to build up brake pad material on the high spots and give that shimmy feeling. Of course, the shop will blame the owner for "warped rotors".
Originally Posted By: Chris142
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
I used to do that.
Now I check parallelism off the vehicle, and runout on the vehicle. The first catches non-flat rotors so I can return them for full refund before I waste time installing them. The second prevents flat&true rotors from being install crooked.
The parallelism check is just 8 more-or-less equidistant measurements with a micrometer around the disc. Your Factory Service manual has the specs, for example the last car I did was < .0015".
Here's a pic of my runout check last week as I installed new rotors on the old Honda Pilot. Again, the runout spec can be found in your FSM. You know, in the parts every shop skips.
What would it cost for a setup like that to check runout, I have done my own brakes for years and never checked. I would have thought with modern machining, runout would be better than years ago, but apparently not.
Is it cost effective to buy that setup for a home mechanic? Where should look for in brands? Where should i look to buy?
Thanks
Originally Posted By: Nissan101
It sucks yes
and i find its ridiculous that oem rotors need to be machined. If i had known this would have been the case, i would have just machined my old ones.
They might have needed to be machined. Or, they may have been installed crooked. In once case I saw, the machine retention screws on a Honda front hub had been broken off almost flush. Almost. The rough surface of the nubs was just enough to hold the rotor crooked and cause shimmy to develop.
3000 miles is just long enough for rotors installed crooked to build up brake pad material on the high spots and give that shimmy feeling. Of course, the shop will blame the owner for "warped rotors".
Originally Posted By: Chris142
We no longer install new rotors with out turning them. Too many are warped or whatever you want to call it right out of the box. Got tired of doing brake jobs 2x.
I used to do that.
Now I check parallelism off the vehicle, and runout on the vehicle. The first catches non-flat rotors so I can return them for full refund before I waste time installing them. The second prevents flat&true rotors from being install crooked.
The parallelism check is just 8 more-or-less equidistant measurements with a micrometer around the disc. Your Factory Service manual has the specs, for example the last car I did was < .0015".
Here's a pic of my runout check last week as I installed new rotors on the old Honda Pilot. Again, the runout spec can be found in your FSM. You know, in the parts every shop skips.
What would it cost for a setup like that to check runout, I have done my own brakes for years and never checked. I would have thought with modern machining, runout would be better than years ago, but apparently not.
Is it cost effective to buy that setup for a home mechanic? Where should look for in brands? Where should i look to buy?
Thanks
Last edited:
Originally Posted By: spasm3
What would it cost for a setup like that to check runout, I have done my own brakes for years and never checked. I would have thought with modern machining, runout would be better than years ago, but apparently not.
Is it cost effective to buy that setup for a home mechanic? Where should look for in brands? Where should i look to buy?
Hi,
Sorry I tried to replay to this the other day, just then Comcast Internet died... so I went to bed. Things have been busy since then.
You don't need really pricey equipment because it's not the actual measurement that matters, it's the difference. So calibration is not a big deal, just backlash.
I have pricey equipment- Starrett and Mitutoyo- but I use cheap stuff on my brakes because it's a hazardous environment for fine instruments, and I don't need 1/10,000th's accuracy. My dial indicator and magnetic base I got separately, but I see they can be had together quite cheap- about $60. I can recommend the Fowler:
https://www.amazon.com/Fowler-Warranty-52-522-101-0-Indicator-Measuring/dp/B00B5HQ45C
You can go cheaper:
https://www.amazon.com/Allstar-ALL96414-0-001-Increment-Indicator/dp/B006K8WANQ
But I have no idea how good they are.
What would it cost for a setup like that to check runout, I have done my own brakes for years and never checked. I would have thought with modern machining, runout would be better than years ago, but apparently not.
Is it cost effective to buy that setup for a home mechanic? Where should look for in brands? Where should i look to buy?
Hi,
Sorry I tried to replay to this the other day, just then Comcast Internet died... so I went to bed. Things have been busy since then.
You don't need really pricey equipment because it's not the actual measurement that matters, it's the difference. So calibration is not a big deal, just backlash.
I have pricey equipment- Starrett and Mitutoyo- but I use cheap stuff on my brakes because it's a hazardous environment for fine instruments, and I don't need 1/10,000th's accuracy. My dial indicator and magnetic base I got separately, but I see they can be had together quite cheap- about $60. I can recommend the Fowler:
https://www.amazon.com/Fowler-Warranty-52-522-101-0-Indicator-Measuring/dp/B00B5HQ45C
You can go cheaper:
https://www.amazon.com/Allstar-ALL96414-0-001-Increment-Indicator/dp/B006K8WANQ
But I have no idea how good they are.
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