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Cruise control downshift points

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Old Jun 17, 2024 | 09:36 PM
  #1  
desertrat's Avatar
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From: Palm Desert, CA
Cruise control downshift points

I have always noticed that the transmission in the HHR will downshift too soon when climbing a hill in cruise. This can cause an abnormally high-reving engine, in my opinion.
When the vehicle is not in cruise the transmission doesn't downshift until a much later point, if at all. I like this a lot better.
My question- is there any way to re-program the transmission control module to a later downshift point, or no downshift at all while in cruise?
Old Jun 18, 2024 | 06:23 AM
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Oldblue's Avatar
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Possibly a tuner could reprogram for different shift points , HP tuners or contact ZZP
Old Jun 18, 2024 | 10:21 AM
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Leave the cruise off if toy don't like it. What do you call high rpms?
Old Jun 18, 2024 | 11:11 AM
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It may be that the cruise control is into the throttle, trying to maintain (or regain) it's set speed, more than your foot would be.
Old Jun 18, 2024 | 11:55 AM
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Originally Posted by RJ_RS_SS_350
It may be that the cruise control is into the throttle, trying to maintain (or regain) it's set speed, more than your foot would be.
Exactly!
Old Jun 18, 2024 | 12:47 PM
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lazaino's Avatar
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From: los angeles
The transmission programming along with the cruise control on ms SS is the most annoying thing on the car. I'd guess because it's programmed for gas mileage and tries as hard as possible to not downshift and when it finally does it seems to go down 2 gears and take off. I notice it mostly when I ask for another 2 MPH and it takes forever to get there so I assume it missed the command and add a couple more and eventually it takes off and I'm suddenly going faster than wanted.
Old Jun 18, 2024 | 03:37 PM
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Don't worry about "excessive" RPM. The computer limits it, if it gets to harmful levels. This is the 21st century.
Figure a way to get 50-60 more horse power to fix it, if you think it is a big problem. Or, set the CC at 55 MPH instead of over 60 MPH; I found it does make a difference, it seems to be tuned for optimal performance between 50-55 MPH.
Old Jun 18, 2024 | 04:11 PM
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Funny thing. I used to love the way the cruise worked when I had my SS. It would never shift gears when going up or down a hill,,,,,,,,,,,, but, I did have a 5 speed. 😄
Old Jun 26, 2024 | 07:54 AM
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desertrat's Avatar
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Some of you don't understand my question, so I will describe it in another way.
I approach a hill in cruise at 70 MPH, the transmission downshifts twice about halfway up, going from 2400 RPM to over 4000+. At the crest it upshifts to normal.
I approach the SAME hill at the same speed without cruise, and the transmission doesn't downshift at all, I just give it more pedal. The engine has enough power to make the grade.
I would like to have the same effect in cruise, just give it more pedal manually without the downshifts, then back off at the crest and let cruise take over again without disengaging cruise at any time.
Some steep hill are the exception, of course. Those should be attempted without cruise in any case.
Old Jun 26, 2024 | 08:03 AM
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I understand your theory, it’s just the application that’s the issue. When I’m on the highway, I don’t engage the cruise control.



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