Just wondering

[fxstc]

Regarding brake pedal pulsing. My wife's 2019 GT2, I drove for a weekend getaway to eastern Washington. Over the cascade mountains. I put it on active cruise control. Thought it was pretty amazing that it would brake and speed up on its own. By the time we reached the other side of the mountain I could feel the pedal pulse. Maybe not the best idea to use active cruise control going down the mountain. Of course the dealer said warped rotors. Any thoughts?

 

[Snicklefritz]

OEM brake pads? You likely have the infamous pad deposits on your rotors. I have not experienced this in over 67,000 miles on original pads and rotors. but there are quite frequent threads and posts on this topic possibly the most brought up topic in the Stinger's lifespan, at least in N. America.

 

[fxstc]

Yes OEM pads. We bought it used with 8200 miles. We have owned it for 3 years. Now it has 20250 miles.

 

[Snicklefritz]

Yes OEM pads. We bought it used with 8200 miles. We have owned it for 3 years. Now it has 20250 miles.

You've been on the forum a while. Have you read this thread at all? FAQ: Vibration under braking: warped rotors? NO!

 

[Volfy]

Not only is descending down mountain passes on any form of cruise control a mighty bad idea, you really should not even rely primarily on the brakes for speed control. We vacation in Colorado and the Arkansas mountains quite often, and I have seen my fair share of cars with smoking brakes at rest stops near the bottom of the mountain. At night, it's not unusual to see vehicles with their brake rotors glowing red hot trucking down the mountain.

Proper way for steep descend is to switch to manual shifting and let engine braking in lower gears control your descent rate. Use brakes only to set entry speeds on turns and to correct overspeed.

All that said... dunno how steep or long your descents were, so no idea what condition your brakes are in. If your dealer service dept have inspected your brakes, they would know better than any of us here. Although "warped rotor" seems like their standard answer given to any customer brake trouble inquiry. If I have to throw darts blindfolded, I'd guess... best case scenario: your brake pads laid down a good bit of deposit on your rotors, as higher temps tend to exacerbate that all-too-common problem. Worse case scenario: your rotors are heavily heat spotted and brake pads utterly toasted.

If you haven't flushed your brake fluid with fresh DOT4 in a while (or ever), now is a good time to do so. You're lucky it didn't vapor lock.

 

[socalvn]

As the others have said great way to overwork your brakes better to run your gears a little bit use those paddle shifters

 

[fxstc]

You've been on the forum a while. Have you read this thread at all? FAQ: Vibration under braking: warped rotors? NO!

Yes I have read a lot of it. Don't recall anyone mentioning active cruise control as a bad idea going down a mountain. Wish I had not used it.

 

[Thomby]

I would recommend finding a nice stretch of road and doing several rounds of aggressive braking, say from 70-80 down to 5mph, not quite hard enough to lock the tires, then cruise a few miles without sitting on the brakes so they can cool off.

9 times out of 10 that'll clean up the rotors and remove the steering wheel vibration.

 

[Snicklefritz]

Yes I have read a lot of it. Don't recall anyone mentioning active cruise control as a bad idea going down a mountain. Wish I had not used it.

I thought that something in that thread might point to pad deposits happening even using CC. It would be ironic if the CC, adaptive or normal, created pad deposits. I know that the normal CC in my GT1 will downshift to 5th gear on extended downhill stretches in order to reduce braking. The adaptive CC in the Premium seems more intent on maintaining distance between the next vehicle. Ima not sure about the downshift to 5th gear happening as regularly, because my driving time in that car is still limited, being mostly local driving. But I will remember this thread and watch to see if it downshifts to 5th gear too.

 

[stoopid]

I'm fairly sure Kia (and most manufacturers) use the brakes a lot in cruise. On downhill I'm fairly sure I've had the car brake rather than downshift the few times I've tried to let cruise do its thing. In those cases I promptly cancel cruise and downshift manually. Active cruise is awesome for heavy traffic and long flat stretches.

 

[See3Pee01971]

Yes OEM pads. We bought it used with 8200 miles. We have owned it for 3 years. Now it has 20250 miles.

I swapped rotors and put on Hawk HPS 5.0 pads. Been perfect ever since. Easy at home job.