Sudden pinch from brakes during otherwise smooth slowdown
 

My XC90 (MY18) is going in for a service this week and I'll be mentioning this issue to the dealer to see if they can work out what it is, but thought I'd ask here first in case anybody else had experienced it and knew what it was or had any pointers.

What happens is that while I'm gradually slowing down or coming to a halt I'll be applying very gentle, smooth pressure to the brakes when suddenly there's a very noticeable point where it feels like the brakes have decided to clamp down much harder than my foot on the pedal and then almost immediately release again back to the 'normal' pressure. It lasts less than half a second and it doesn't happen every single time but maybe about a third of the time. Some days not at all, other days almost every time.

It's so sudden that it almost feels like hitting a bump or pothole but without any up/down motion.

I don't think it's any of the auto safety measures kicking in because I don't get any of the warning signs on the dash/HUD or any info in any of the displays to say they're kicking in, and I've experienced plenty of false positives from the auto collision warnings so I know what they look and feel like, and his isn't doing that at all.

Anybody else had this or know what it might be?

Mine feels a bit like that when the stop/start cuts the engine just before you're actually stopped.

Ah, I have stop/start disabled all the time. Well, that is to say I manually disable it every time I drive. Good suggestion though, thanks.

Does you Model have the auto-hand brake function that can be set to auto apply the handbrake as you are “stopping” which may appear to be cutting in too soon.
I normally have mine turned off as it makes it hard to park in my garage when I am inching forward to a very precise stopping place.

Yes, I have that function and like it a lot, use it all the time. I guess it’s possible the car is thinking it needs to cut in and then immediately changing its mind perhaps. But i’m Usually doing about 10mph at the point this issue occurs.

Switch it off for a few days to rule it out.

Are you sure it's the brakes & not the transmission dropping into a lower gear ?

Could be I guess but seems very clunky for an automatic. Shame the dash doesn’t tell you what gear it’s currently in so I could tell.

Does the rev counter show the revs increasing when it happens? As Andy says, it does sound like the transmission is dropping a gear or two as you slow down.

Do you have Eco mode? If you do and it works like my V60, it disables engine breaking and presumably stop this happening.

I hope that helps.