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Car shudders on braking. New discs/pads all round or more to it? Car is 2015.
BMW F31 330d brake shudder
- Thread starter the_worrier
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Soldato
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you tried re bedding in the pads?
That's done a low speed, I really doubt it would show anything.
If they are brand new, was the hub cleaned as it sounds like the discs might not quite be flat...
It does.
how?
I had this on an F31 330D tourer 2017.
New discs and pads. Mine was an M Sport so had the bigger blue caliper'd brakes.
Thought the discs may have come warped from factory, 2nd set of brand new discs fitted, same judder.
I think in the end the front hubs were changed - I think! This cured it though.
New discs and pads. Mine was an M Sport so had the bigger blue caliper'd brakes.
Thought the discs may have come warped from factory, 2nd set of brand new discs fitted, same judder.
I think in the end the front hubs were changed - I think! This cured it though.
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Not all at, the rollers run at 5mph and it’s more than enough to pick up fluctuation/grabbing.
I don’t think he’s had new discs yet.
If he has, it could be the hubs weren’t cleaned properly or one is warped, which is more common than you may think.
One other thing to bear in mind for anyone who cares to read this..
We had a problem with a lot of sales cars with judder when I worked at a Merc dealer.
It turned out the company refurbishing the wheels were power coating the hub face as well which turned out uneven and caused the problem.
We had a problem with a lot of sales cars with judder when I worked at a Merc dealer.
It turned out the company refurbishing the wheels were power coating the hub face as well which turned out uneven and caused the problem.
Soldato
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It's common for the inside face of the disc to be heavily corroded when the outside looks OK, run your finger down the inside disc surface to check. Mine look great on the outside but the inside looked like it was from the bottom of the ocean and new discs/pads sorted out the vibration I was getting when braking.
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I have bought 4 new discs and 2 sets of new pads but not fitted them yet.
Sounds like you worry a lot.
A car travelling at 60mph will require x amount of energy dissipation to slow down. A car "travelling" at 10mph will require 10x the energy dissipation to slow down. Pop the car on some rollers, apply 6x the amount of force, and you'll find the cause of the judder.
This is of course a massive oversimplification, but that's generally how it works. Even shorter answer? Physics bro.
A car travelling at 60mph will require x amount of energy dissipation to slow down. A car "travelling" at 10mph will require 10x the energy dissipation to slow down. Pop the car on some rollers, apply 6x the amount of force, and you'll find the cause of the judder.
This is of course a massive oversimplification, but that's generally how it works. Even shorter answer? Physics bro.
I had an issue with my 5 series after a pad and disk swap early into ownership. It was quite pronounced but ended up being pad build up, which though took time to go away it did in the end and they performed like normal. When it first occurred a week or so after the swap I wondered if I had overheated them etc, and they did get quite bad but in the end it sorted itself.
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Good call. I don’t have a press to get the old bushes out and then the new ones in so may have to change the whole wishbone. I’m having difficulty seeing which one’s I need as there are several
Check your lower control arms first, before you spend any money, its a very common fault, considering the age of your car they're most likely gone. I put strongflex polybushes in mine, night and day difference.
In this shape.