Cruise control on 2015 Corolla CVT question

[NissanMaxima]

Hi all:
So after taking a road trip in our 2015 Corolla S+ with CVT transmission, I observed something I wanted to ask the forum. When locked in on cruise control and going uphill, rpm's would go up and you could hear the engine roar as presumably the CVT was selecting a lower "gear". That makes sense to me in order to maintain power and therefore speed. However, on the downhills, it would do the same. Is this basically engine braking to ensure the set speed was not exceeded? It was so unnerving at times that I took it off cruise control at times at the rpm's would really rev high and I could do a better job on my own by just backing off on the gas.

 

[dparm]

Yes, because the cruise control systems generally have no way to apply the brakes, so they can only dial the speed down by engine braking.

 

[LotI]

Hill logic...the machines are taking over. There is a T1000 at your door right now, I would suggest not opening it.

 

[old1]

Yes, my 2014 Fusion does that also. It seems that if the downhill is so steep that completely backing off the accelerator won't hold the speed down to the set speed it will downshift.

 

[NissanMaxima]

Thanks all: I figured it was engine braking but was baffled because I could easily maintain downhill speed at my set speed by disengaging cruise and simply backing way off the gas. I guess humans are still better than Terminators in some regards??

 

[JTK]

I've found my late model Subaru CVTs to have a lot of engine/compression braking ability to them as well. Much more so than my conventional step automatics.

 

[Nick1994]

Yup it doesn't want to go faster than your preset.

My Sonata isn't CVT but it downshifts with cruise on downhill. Drives me nuts. I can manually select 6th gear though and it'll cooperate.

 

[PeterPolyol]

Grade Logic. Welcome to 1995's Honda.....

 

[CR94]

I drove a friend's circa 2001 Chrysler that did the essentially same stupid trick with its 4(?)-speed conventional automatic, downshifting to rigidly maintain the set speed even where coasting down faster in the top gear would be safe and legal. Apparently all cruise controls do this nonsense now? My Prius does its version, heavy regenerative braking (or effectively downshifting for added "engine braking" if the battery is "full") when it's not needed.

 

[Jim K]

All cars I`ve had do the same thing with the shifting going up and down hills with cruise on.