Brake time!
- Thread starter solekeeper
- Start date
- Car
- 2004 FX35 AWD
- Name
- John Green
Even new rotors can have rotor runout see the info below.---
BRAKE JUDDER-
• Brake Judder is caused by rotor thickness variation and/or rotor run out.
pulsation. In severe cases it can also cause a back and forth oscillation in the steering wheel.
tightened, especially with an air impact wrench.
•
When installing a new rotor, a rotor that has been surfaced off the car, or a rotor that has been
removed for any reason, use the following indexing procedure to ensure the minimum amount of rotor run-out.
1. Make sure the rotor is fully contacting the hub. Clean the rotor-to-hub surface if it is rusty.
2. Install the rotor and all lug nuts. Tighten the lug nutsto 40 ft-lbs (for this indexing process only).
3. Place a reference mark on the rotor and hub.
torque to 40 ft-lbs (again, for this indexing process only).
Repeat step 4 and 5 until the rotor is positioned with the least amount of runout.
---------- Post added at 10:14 PM ---------- Previous post was at 10:02 PM ----------
Runout Inspection--
inside the disc edge.]
BRAKE JUDDER-
• Brake Judder is caused by rotor thickness variation and/or rotor run out.
Rotor Thickness Variation: When the inner and
outer surface of the rotor are not flat and not
parallel, the brake pads will travel in and out as
they follow the low and high spots on the rotorouter surface of the rotor are not flat and not
parallel, the brake pads will travel in and out as
Rotor Run Out: If the brake rotor is not true to
the hub center, the brake pads contact one point
on each side of the rotor with each wheel
rotation, even if the brakes are not applied. Over
time, this point contact will cause the rotor to
wear more in these areas and cause rotor
thickness variationthe hub center, the brake pads contact one point
on each side of the rotor with each wheel
rotation, even if the brakes are not applied. Over
time, this point contact will cause the rotor to
wear more in these areas and cause rotor
•
This motion of the brake pads is transferred through the caliper pistons and is felt in the brake pedal as a
pulsation. In severe cases it can also cause a back and forth oscillation in the steering wheel.
•
Another contributor of brake judder is lug nut overtorque. This can occur if the lug nuts are over
tightened, especially with an air impact wrench.
Brake Judder Repair
•
Brake judder issues must be corrected by turning the rotors with a ProCut™ PFM series On-Car Brake
Lathe.
Lathe.
•
Refer to ITB04-038 for additional information on using this lathe.
•
If the rotors are replaced, make sure you index them to the axle hub to ensure minimum runout
ROTOR INDEXING--
When installing a new rotor, a rotor that has been surfaced off the car, or a rotor that has been
removed for any reason, use the following indexing procedure to ensure the minimum amount of rotor run-out.
1. Make sure the rotor is fully contacting the hub. Clean the rotor-to-hub surface if it is rusty.
2. Install the rotor and all lug nuts. Tighten the lug nutsto 40 ft-lbs (for this indexing process only).
3. Place a reference mark on the rotor and hub.
4. Measure rotor run-out with a dial indicator. Ifthe run-out is above limit continue with step 5.
5. Remove the lug nuts and shift the position of the rotor one lug clockwise, then reinstall the lug nuts and
torque to 40 ft-lbs (again, for this indexing process only).
Repeat step 4 and 5 until the rotor is positioned with the least amount of runout.
6. After you find the position with the least amount of runout, if the runout is still more than the limit you’ll need
to turn (resurface) the new rotors using the ProCut™ PFM Series on-car brake lathe.
---------- Post added at 10:14 PM ---------- Previous post was at 10:02 PM ----------
Runout Inspection--
1. Using wheel nuts, fix disc rotor to wheel hub. (2 or more positions)
2. Inspect runout using a dial gauge. [Measured at 10 mm (0.39 in)inside the disc edge.]
Runout limit
(with the disc rotor attached to
the vehicle)
: 0.04 mm (0.0016 in)
Runout limit
(just the disc rotor)
: 0.02 mm (0.0008 in)(with the disc rotor attached to
the vehicle)
: 0.04 mm (0.0016 in)
Runout limit
(just the disc rotor)
NOTE:
Make sure that wheel bearing axial end play is within the specifications
before measuring runout.3. If runout is outside the limit, find the minimum runout point by shifting mounting positions of disc rotor and
wheel hub by one hole.
4. If runout is still out of specification, turn rotor with on-car brake lathe. wheel hub by one hole.
- Car
- 05 FX35 RWD
I just threw on some Hawks on the rear. Went smooth enough. Took me about 45. If you DIY, dont forget to grind the edges of the pads. I didnt need to turn the rotors since it's just the rears. The sound sensors at the end of the old pads were embarrassingly loud.
teknoboy66
Member
Did you set your pads after you installed them?
That's very important if you're using the old rotors.
After installing new pads make 6 to 10 stops from approximately 35 mph with moderate pressure. Make an additional two to three hard stops from approximately 40 to 45 mph. Do not allow the vehicle to come to a complete stop.When completed with this process, park the vehicle and allow the brakes to cool completely before driving on them again. Do not engage the parking brake until after this cooling process is compete.
EDIT:
I just remembered that I need to change my front pads as well.
I noticed everyone here likes the OEM pads over Hawks. Does anyone have experience with EBC pads?
I had them on my G35 coupe and loved them and so I'm curious why they wouldn't be any good on the FX35
That's very important if you're using the old rotors.
After installing new pads make 6 to 10 stops from approximately 35 mph with moderate pressure. Make an additional two to three hard stops from approximately 40 to 45 mph. Do not allow the vehicle to come to a complete stop.When completed with this process, park the vehicle and allow the brakes to cool completely before driving on them again. Do not engage the parking brake until after this cooling process is compete.
EDIT:
I just remembered that I need to change my front pads as well.
I noticed everyone here likes the OEM pads over Hawks. Does anyone have experience with EBC pads?
I had them on my G35 coupe and loved them and so I'm curious why they wouldn't be any good on the FX35
Last edited:
teknoboy66
Member
I apologize, I said "set" but I meant "bed".
Here's a link that tells you why it's important to bed-in your brake pads and how to do it.
http://www.zeckhausen.com/bedding_in_brakes.htm
I've done this every time I've done a brake job and have been very satisfied with the results.
- Car
- 2004 FX35 AWD
- Name
- John Green
Out of the Manual----
BRAKE BURNISHING PROCEDURE
Burnish brake contact surface according to the following procedure after refinishing or replacing rotors, after
replacing pads, or if a soft pedal occurs at very low mileage.
replacing pads, or if a soft pedal occurs at very low mileage.
CAUTION:
Only perform this procedure under safe road and traffic conditions. Use extreme caution.
1. Drive the vehicle on a straight smooth road at 50 km/h (31 MPH).
2. Use medium brake pedal /foot effort to bring the vehicle to a complete stop from 50 km/h (31 MPH). Adjust
brake pedal /foot pressure such that vehicle stopping time equals 3 to 5 seconds.
3. To cool brake system, drive the vehicle at 50 km/h (31 MPH) for 1 minute without stopping.
4. Repeat steps 1 to 3, 10 times or more to complete the burnishing procedure.2. Use medium brake pedal /foot effort to bring the vehicle to a complete stop from 50 km/h (31 MPH). Adjust
brake pedal /foot pressure such that vehicle stopping time equals 3 to 5 seconds.
3. To cool brake system, drive the vehicle at 50 km/h (31 MPH) for 1 minute without stopping.
teknoboy66
Member
thanks for posting that. The procedure is different for every type of pads and so I'd assume this is the procedure for OEM pads.
- Car
- 2003 FX35T
- Name
- Brad
When I did my Stoptech BBK and hawk rear pads, Stoptech recommend the above burnishing procedure. Says NOT burnishing will shorten the life of the pads. I followed the procedure and the brakes are great. My only complaint is the amount of dust. I will also return to OEM pads in the rear the next pad change. The hawks are even dustier than the Stoptech front pads.