Vibration through steering wheel during light braking.

[SomeGuy537]

Hello, i have a problem with my 850 where i get vibrations through the steering wheel during light braking. They get stronger if i brake lightly from high speed and seem to get worse after driving for a little while. Any clues?

[MoVolvos]

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Warped rotors or suspension like tie-rod or ball joints.

With both our 03 Honda Odyssey and Lexus GS 300 injecting grease into the rubber boots of the various suspension component got rid of the vibration. Both suspensions are sensitive to a small amount of suspension wear and translates into steering vibration rather than brakes. You can try this first.

Inject and massage grease into joint. Wipe excess that comes out. Before greasing test to make sure the part has not failed to the point requiring replacement already. If the vibration goes away you know the part is the culprit and could need to be replaced.

https://www.amazon.com/Lucas-Oil-10005- ... 68&sr=8-10

https://www.amazon.com/Lumax-LX-1416-Si ... 163&sr=8-8

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[LOB]

It does not have to be warped rotors (or suspension parts) it might also be the caliper which does not move freely.sideways on the slide pins, seized brake pads etc. Before you do anything else. Do a small overhaul of your brakes.

[MoVolvos]

It does not have to be warped rotors (or suspension parts) it might also be the caliper which does not move freely.sideways on the slide pins, seized brake pads etc. Before you do anything else. Do a small overhaul of your brakes.

It's not difficult to remove one caliper bolt and flip up or pull off the caliper up to check for seized brake pads or glide pins. If either is seized the piston will travel further in order make up for the gaps in the seized parts so unlikely to cause that much pulsation in the steering wheel.

Don't spend money on an overhaul yet unless the parts are worn. If the parts are indeed seized you can just lubricate the pad ears and glide pins (little sanding if needed) to restore movement and test. Very unlikely to make the steering shake but can give it a try regardless.

If it works then no parts were needed. If the shaking is still there check suspension and runout of rotor. The goal is to find the problem and not parts swap to figure things out.

The OP did not mention brake pulsation? Either too much steering shake so he is not noticing it or it is very little or none at all so brakes is not the first place to look but still should be looked at.

Neighbor's son has a 2010 P71 Interceptor. Two years in and he had put on 2 sets of tires 2 at a time then front brakes. With each new parts the pulsation in the brake pedal improved some. I told him it could be rear brakes but there were no signs of wear and pads still looked good. Since the new fronts were slotted and drill he decided to replace the rears with the same.

Yes, the rear brakes were the cause and he was so surprised. He told my Son that he can't believe how smooth it was and how terrible it was to live with it for 2 years.

Check everything.

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