I've noticed with my new-to-me 2018 that when doing a slow crawl to a stop, the brakes start getting jerky when getting near 10ish mph and slower. Is it trying to do an assisted stop because it detects a car in front of me? Doing regular non-crawling stops I don't feel it. Happens in both dynamic and regular mode. Or is something wrong with the vehicle?

 

Can you do some slow crawl stops without cars in front of you, to eliminate that as a cause?

 

I've noticed something similar when in dynamic+sport mode when coming to a stop probably in the 10MPH range where the brakes come off as feeling jerky or grabby. This only happens when in dynamic+sport mode when not using the paddles; seems to me it's downshifting while doing the throttle blip thing and this contributes to the sensation. I've never noticed it doing it in regular or just dynamic mode though.

 

I'll test it on the way home today with no cars in front plus using paddles. But it does it at such a low speed I'd assume it's in 1st gear by then.

 

You might be surprised, when I described the sensation I'm feeling I think it's occurring on the 3-2 downshift as when in dynamic+sport it never shifts into 1st when coming to a stop unless I knock it down into 1st using the paddle.

 

I think it is the factory pads....they definitely 'grab' at low speeds (as, when stopping in a garage). The mat on my garage floor always crunches up, under the Jag.

Supposedly, changing to Porterfield P4s pads minimizes the 'grabby' effect, without affecting high-speed brake effectiveness significantly...

 

That is exactly what is going on. Once I switched to the Porterfield pads the grabbiness went away.

 

I notice this too, and you are correct it never downshifts to first.

 

I have the R coupe AWD and the jerking when doing gentle slow speed stops is definitely from the 3-2 auto downshift. Whether the trans is in S or D, mode in dynamic or normal, the jerk occurs and I see the tach blip at the same time. Try doing the same in manual mode in 2nd gear and this won't happen.

 

Hi, im having the same issue on my 2011, did you ever figure it out?

 

At a recent HPDE at Watkins Glen, one of the most experienced instructors described a technique he called "monkey toes", where you gradually roll your toes (inside your shoe) onto the pedal and lightly pressing the pedal in a progressive way with your toes before actually feeling like your whole foot engages. He did this for both application of the gas and brake to achieve more smoothness and greater control. I've been trying this on the street I am definitely a smoother driver. Maybe try this? You might be surprised. I was.

 

I found the stock brake pads to be initially grabby at low speeds, particularly noticeable in stop and go traffic. The Porterfield R4S pads are much better there. The only complaint I have with them is that when the brakes are cold and *very* wet they don't work that well. I've only noticed it after 15+ minutes on the freeway in torrential rain, and need to dry the brakes before exiting so I can stop as I expect. We haven't had much of that weather lately.