Cruise control downshift points
06-17-2024, 09:36 PM
#1
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Thread Starter
Join Date: 09-25-2009
Location: Palm Desert, CA
Posts: 103
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?
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?
06-18-2024, 12:47 PM
#6
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Join Date: 03-08-2008
Location: los angeles
Posts: 219
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.
06-18-2024, 03:37 PM
#7
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Join Date: 01-23-2009
Location: Fredericksburg,VA
Posts: 24,942
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.
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.
06-26-2024, 07:54 AM
#9
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Thread Starter
Join Date: 09-25-2009
Location: Palm Desert, CA
Posts: 103
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.
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.