Pulsing brakes at highway speeds

Discussion of Infiniti's amazing (and underrated) sport-luxury crossovers, the EX35 and EX37. For 2014, the EX series will be renamed QX50, in line with Ininfiit's new naming conventions.
TrevEB
Posts: 33
Joined: Mon Feb 25, 2008 9:41 am

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This topic has been touched upon in the past. Just want to followup on the correct diagnosis.
We feel a pulsing sensation when applying the brakes, most noticeable at highway speeds.
It feels like grip/release/grip/release.
As if the brake pads are rolling over a bump on the rotars causing the pulsation.
I cannot determine which of the 4 brakes the pulse is coming from.
It’s been growing stronger over the last couple years. No one believed me when I first noticed it. Car shops, tires replaced, and the wife all said they could not feel it.
Well, now the wife feels it. :)

So, yes mostly likely warped rotors?
Was there any quiet recall for this issue years ago?
I thought I had come across the topic earlier and that I was to late to the party.


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AZhitman
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"Warped" rotors is typically the first thing people think of. However, it's a big deal to "warp" a rotor.

More often than not, it's a transfer of material from the pads to the rotor face from sitting, driving through a big puddle with hot brakes, or... well, disuse.

Start with a good visual inspection. Rotor surface should be clean, glossy, with faint concentric lines around the face. If you see any anomalies, inspect closer. I have in the past pulled the wheels and run the car in drive on a lift to inspect for rotor runout.

If all else fails, perform a "brake bedding" procedure (Google) such as what you'd do when installing new brake shoes. If that doesn't square it up, new rotors are inexpensive.

TrevEB
Posts: 33
Joined: Mon Feb 25, 2008 9:41 am

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A followup to this topic.

Dublin Infiniti diagnosed the problem coming from the rear rotors and had them resurfaced.
The problem almost but not entirely went away.
1 year later we had the front rotors resurfaced.
Now the problem is completely fixed.

So, if you are feeling the pulsing brakes problem, its probably best to have all rotors resurfaced at once.

z32S
Posts: 9
Joined: Thu Mar 24, 2022 11:21 am
Car: ???? Infiniti EX35

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best would be when applying brakes, take it easy and be gentle... sudden brake application will wrap rotors and we all know when metal heats up it'll expand which will get more 'rotor runout'


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