Cruise Control Weirdness

[BlaydeX15]

So I was driving down the canyon last weekend with cruise on at ~70ish, and hit a pretty steep section. Wasn't really paying attention to my speed, but when I looked down and checked it, I was going ~85 and cruise control had cancelled itself. The car will regularly hit cruise speed +4 on downhills before it bothers downshifting (Does it brake?), but this is the first time I've ever seen the car give up and turn cruise off!

Of course, there is a non-zero chance that I accidentally turned it off on accident, but who knows. Lol.

Anyone notice anything similar, or am I just a one-off?

GT without tech package BTW, so just normie cruise control.

 

[MerlintheMad]

I've seen the cruise allowing excessive speeds downhill a few times. But actually turned "off"? I haven't noticed that, yet. I have noticed that to maintain cruise downhill, the shifting becomes unresponsive, i.e. cruise takes precedence. You can't get the paddle shifters back until the downhill episode is over (or of course you can turn cruise off entirely).

 

[mldavis2]

Mine does brake if the cruise set speed is exceeded by about 5 mph or so (guessing.) It also seems to do a fairly good job of either downshifting or maintaining a lower gear if you are descending and have to brake. It seems there is not as much engine braking on this little 3.3T when using manual downshifting as there is with my big 6.0L LS2 6-speed or my previous 6.0L LS96 6-speed automatic. This is probably because it is a lower compression engine that uses turbo boost to maintain the desired compression ratio rather than having higher static cylinder pressures.

 

[BlaydeX15]

I've seen the cruise allowing excessive speeds downhill a few times. But actually turned "off"? I haven't noticed that, yet. I have noticed that to maintain cruise downhill, the shifting becomes unresponsive, i.e. cruise takes precedence. You can't get the paddle shifters back until the downhill episode is over (or of course you can turn cruise off entirely).

Yeah, I'm wondering if I just tapped the brakes without noticing. I brake hover while CC is on (Has saved my ass from many many deer), so it's possible.

Nice to know going +5 on cruise is the norm though. It's sooo going to get me pulled over, since I usually set cruise at 7-8 over. Lol.

 

[MerlintheMad]

@BlaydeX15 Yes, I think you tapped the brake and disengaged the cruise. I think that is what happened those few times I've seen myself going well over the cruise setting downhill. I say this with confidence, because the instant I notice that the car hasn't downshifted to maintain cruise, i.e "I am going too fast!", I use the brakes to get back down to cruise speed. I have yet to look at the cruise setting to see if it is still set, as my first reaction.

I typically set my cruise at +9 above the speed limit.

 

[Mach_Tuck]

Smart cruise with the tech package certainly applies brakes as my car will come to a complete stop with traffic should that be the case with no intervention from me.

 

[Paul32]

Smart cruise with the tech package certainly applies brakes as my car will come to a complete stop with traffic should that be the case with no intervention from me.

Yes.

 

[Mach_Tuck]

Yes.

Sorry, that wasnt a question...i was trying to say that the car will apply the brakes on its own should the conditions (car in front of me slows down or stops) warrant the brakes to be applied.

Cheers

 

[MerlintheMad]

This is all described in Forward Collision-Avoidance Assist (FCA) starting on page 5|64. It clearly describes how the car will take over and brake under smart cruise control conditions, or if the driver is not responding to what the car "sees" as a developing situation, etc.

 

[Kazz]

Cruise does apply the brakes - to the point of burning up your pads on lengthy downhill sections if they're long and steep enough. I use my feet on big downhills and re-establish the cruise when I'm off them.