I have a 2009 XF and have been the only owner. For as long as I can remember I've had an issue where the steering wheels wobbles or vibrates like crazy when I brake. Every mechanic tells me that it's warped rotors but I've had the rotors and brake pads changed a few times and the issue hasn't gone away. I also notice a very slight vibration in the steering wheel while driving but it isn't significant. I've changed and balanced numerous sets of tires over the years with alignments and that isn't the issue.

I do have aftermarket rims so I recently put the original tires and rims on to see if that would correct the issue. Once again...no luck.

I'm at my wits end trying to figure out what the issue is. My buddy who is a former mechanic recently helped me replace the upper control arms and upper strut mounts about a month ago. He was all up in there looking at everything. There was no play anywhere that he could find.

Does anybody have any idea as to what could be causing this? It's been driving me crazy for so many years.

 

That is a classic sign of uneven rotor wear. Could be a brake caliper sticking and overheating part of the pad but your mechanic should have spotted that

Given all you've done I'd suggest two possibilities
1) rust or other obstruction on the surface of the hub where the rotor goes on such that one (or more) of your rotors isn't quite square. That would generate wobble. You can get a round sanding device to attach to an electric drill which sands around each stud.
2) worn wheel hub could also cause wobble. Sometimes not obvious that one of them is worn

 

Lots of discussion about "brake judder" over on the Pommy forum and the general consensus is there are two major causes:
1. Brake pad material deposition on the rotors/discs. Very often incorrectly called "warped discs" but it ain't that, it's almost impossible to warp a disc.
Happens when you get the brakes nice and hot then you stop with your foot on the brake pedal and/or you apply the EPB.
In bad cases you can see the imprint of the brake pad on the disc. These deposits/imprints then get hotter than the surrounding areas under medium to heavy braking and cause judder.
But you (Enzo) have replaced the discs are few times so this is unlikely to be your cause.
Which leads to cause # 2:
2. Sticking/jammed caliper slide pins. Very common and opinions are now leaning towards this as being the main cause.
Easy enough to test and maybe even fix - remove the slide pins, clean out the plastic sleeves in which they fit, lightly grease the slide pins with dedicated hi-temp ceramic brake grease (I use Bendix) then refit.
I'm betting this is your cause.

 

I can only tell you how I fixed my brake pulsing problem and that was to adjust the self adjusting rear brakes. If you are light on the brake pedal when backing like me you need to find a spot where you can back up safely and apply a little extra pressure on the brakes so the rear brakes can readjust. It worked for me.

 

In line with Britcars thinking, has your mechanic used a dial indicator to measure the run out on each rotor? You can even do this on new rotors immediately after placing it on the hub. This would tell you if there is a problem seating the rotor flush onto the hub. I personally have seen decent improvements in my rotor alignment merely by testing the rotor at each position on the hub (ie rotating it one stud at a time).

 

^^This^^ No. #2
Very well known issue on earlier X-250 s.

 

lower forward control arm bushing might cause the vibration when u brake,

 

I agree with all the ideas above. I would re-grease your slide pins and check rotor runout at the same time. If this is fine I would look at your control arms. In my case upper control arms contributed to weird braking (uneven braking and lurch near end of braking). Once they were replaced symptoms were gone.

 

I recently picked up my shiny new 2013 XF 275ps 3ltr and had a similar problem when breaking at pace, I am not heavy on the breaks but ether heavy or light breaking the vibration has gradually become more apparent. I had the disks and pads replace under warranty and this stopped it for a while but has now started again and its out of warranty. Being a lazy @rse I havent bothered to look closely at the culprits yet mainly due to not having the time but would make sense if there is a sticking pin somewhere. I do tend to usually overhaul the breaking system and will do a fluid change as I dont know when / if this has been done and have a play with the calliper's to see if they move freely as they need painting again anyway. Will report back with the findings when done. Im also looking for a reputable independent to do my timing but will start a new thread on that if anybody can recommend?

 

I fixed issue with the caliper pins light sanding and grease. If it vibrates when not breaking I would check a bent wheel minimal as it may be it will cause vibration.

 

Try bedding your brakes. It works! Try it.

https://www.autozone.com/diy/brakes/bedding-brakes

 

It has been 3 years and many, many miles and the pulsing has not returned and it did not cost me a dime.

 

There's no vibration otherwise, only when braking. Nice and smooth as should be when driving. Doesn't feel ball jointy ether so going with the pins.. Fingers crossed

 

Interesting, Ive always done a (break TEST) for wants of a better word, when I've changed my breaks and this is more or less what that article is saying to do. I dont actually know if the repair shop did this so going to have a good look now the weather is ok and see give them a good clean up while doing it all. I was under the impression all 275s had red callipers but mine are just standard colour so Im wondering if there's been some changes beforehand.

 

once I learned this trick I have cured may “warped rotors”. It really works. It takes care of the brakin shake!

 

Yes occasionally I get some brake pedal judder and doing a few hard stops usually cures it. Seems like when I just drive around town and use the brakes easy after awhile I notice it starts to shudder a bit.
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Yep, a good ol' Italian tune up doesn't just apply to the engine it also helps the brakes.

 

yup. When the brakes are HOT and you stand at a light with the brake pushed down youre building up that judder

 

I have the same problem with my Jag and with my Kia, it’s the discs they warp very easily. It’s rubbish metal they use.

 

will you just trying “bedding the brakes” please? Youll see it eliminates the problem and costs you NOTHING