Automatics also have hill hold!
- Thread starter atvman29
- Start date
theenico
New member
That's just kind of inherent in the design of an automatic. Because the car is always in gear and the way the torque converter works, it will generally sit in place on a decent incline. This same reason is why an automatic will creep forward on a level surface. No hill hold there, just a properly functioning auto tranny.
atvman29
New member
Beg to differ... The incline was probably greater than 35 degrees and upon releasing the brakes the car would stay stuck in place for 2 seconds and then there was a noticeable release and the car started rolling backwards.
I realize this wouldn't happen on a normal hill but on one this severe, I definitely noticed it.
I realize this wouldn't happen on a normal hill but on one this severe, I definitely noticed it.
theenico
New member
I work for GM. I'm pretty confident that it is not a feature on the A/T equipped Sonics.
A good way to confirm/deny this is to try it again with both TCS and Stabili-trac turned off. If it "holds" again, then I am definitely correct. On the manual trans cars if you turn of TCS and Stabili-trac, it also disables the Hill Hold feature.
laborsmith
New member
But note that in the Sonic Ordering Guide the Hill Hold Feature is S for standard in every trim, auto or manual, sedan or hatchback.
When I first saw that I questioned it thinking why would they have it in an auto trans, but apparently real life tells us they do.
Laborsmith
When I first saw that I questioned it thinking why would they have it in an auto trans, but apparently real life tells us they do.
Laborsmith
Sorry, you are wrong there. (I am on the Sonic program team). It IS on all Sonics - both MT's and the AT - standard equipment. Since ABS is standard, the EBCM controlls this feature regardless of transmission.
The way to tell it is working it to get on a hill greater than 5-7%. Hill hold will engage once you come to a COMPLETE stop. If you lift your foot off the brake, it wil hold for 2-3 seconds, then release. You will feel it release as you start to roll back.
Of course it is most useful with the MT, giving you time to get into the gas as you let out the clutch, but you will also notice it on steeper hills (San Francisco anyone??) with the AT. Of course an AT does not roll back as fast as the MT, but it is still nice to prevent rollback.
atvman29
New member
Interesting, but what purpose would it serve? How long does it take to move your foot from the brake to the gas?
It was nice on the very steep incline of a crowded parking garage exit after a Minnesota Wild game (WIN!!).
Some of the other vehicles would spin their wheels going for the gas because it was so steep.
laborsmith
New member
You are talking about the auto trans cars, right? Or you have never had the driver behind you crowd you while stopped on a hill when driving a manual?
I suspect the technology is hard wired in, but anyways I know I would appreciate hill hold when driving a manual trans vehicle.
Laborsmith
I suspect the technology is hard wired in, but anyways I know I would appreciate hill hold when driving a manual trans vehicle.
Laborsmith
theenico
New member
Since it's tied to the EBCM, that makes sense. No point in having two different controllers.
Oh well, I can deal with being wrong. I've been married for almost ten years, so this is nothing new.
