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View Full Version : Stock Auto Tranny Downshift adjustments


emarkay
April 19th, 2006, 05:20 AM
With gas being over $3.00 a gallon now and going up, I want to mod my downshift points. I know I could 'figger' it out, but can anyone point me directly to the tables and some rough settings?

I want to keep part throttle downshifts exactly as is (stock) but I want to prevent "passing gear" (showing my age) (the 4-3-2 downshift) from happening until 90% throttle or above, at any RPM/MPH.

Maybe also want to modify 4-3 and 3-2 to downshift a bit higher in the RPM band, but that is MUCH lower priority.

These engines have gobs of torque and I hate that the stock calibration puts passing gear at about 60% throttle (SOTP estimate).

I know it may cause some traction issues, but I do have traction control "on" and Torque management still enabled.

Thanks!
SSpdDmon
April 19th, 2006, 08:12 AM
It'll feel weird, but if you want to do it....just reduce the part throttle downshift tables (all cells except the last two). Look at the 2>1 shift for example. In stock form, it will not downshift into the lower gear (1st) unless you are under 10 mph or you give it 100% throttle. Just my opinion....
joecar
April 19th, 2006, 09:05 AM
Make sure D0960, D0961, D0962 are set to 100%.
emarkay
April 19th, 2006, 12:07 PM
Why it will feel wierd? I spent 7 years with a 1965 Impala... 2 speed powerslide....

Just want to make it REALLY mean it when I floor it...
caver
April 19th, 2006, 04:20 PM
I do that for all my customers with auto boxes. The kickdown everytime you give it a sniff of gas is annoying as hell.
emarkay
April 20th, 2006, 02:12 AM
I do that for all my customers with auto boxes. The kickdown everytime you give it a sniff of gas is annoying as hell.


So you agree with the above info? If not PM or email any differences, if you don't want to leak a 'trade secret' I'll keep it under my hat (hood/bonnet) :)
caver
April 20th, 2006, 04:33 AM
No trade secrets I just change the throttle based downshift tables to near 100% in normal mode.
Performance mode I leave the kickdown alone and move the rpm based upshift point closer to the rev limiter and reduce the torque reduction by 50%.
The idea is normal mode is less frenetic and performance mode is there for when things get serious