Downshifting to Slow the Car Down?
03-17-2009, 10:03 AM
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When driving manual mode I often downshift to slow the car down. Does this out excessive strain on the transmission?
Thank you
-Krozi
Thank you
-Krozi
03-17-2009, 10:10 AM
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Originally Posted by Krozi' post='819297' date='Mar 17 2009, 01:03 PM
When driving manual mode I often downshift to slow the car down. Does this out excessive strain on the transmission?
Thank you
-Krozi
Thank you
-Krozi
03-17-2009, 10:13 AM
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Originally Posted by jfk92' post='819305' date='Mar 17 2009, 02:10 PM
I was taught to downshift using the engine to brake the car a bit when I learned to drive a stick. I can't see why the same principals don't apply to the 'chick-stick' mode on today's cars. instead, the computer engages the clutch and releases it once in gear I suppose. I'd be leery of slamming it down, i.e. causing a massive rpm spike for the gear...that'd strain any trans initially...question I have is how would the clutch behave in these cars....a true stick you can ride it until you see smoke coming from your engine bay..if you aggressively downshifted the car would the clutch release be gradual to prevent heavy load to the trans and therefore wear or ..... ? an interesting question for sure.....i've basically provided no discrete answer though...my thoughts.
03-17-2009, 11:22 AM
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The problem with the regular Steptronic (not the Sport Auto) is that it does not rev-match. On this basis, while the car will intervene and will not let you over-rev the engine when you change down, an aggressive downshift within tolerance can indeed put some additional strain on the drivetrain. Sport Auto applies a throttle blip to rev-match on a downshift and thus there is no additional strain placed on the engine or the transmission. In reality there's little reason to downshift while braking and decelerating with the standard Steptronic - the transmission will downshift as it needs as the car slows - other than wanting to be in a lower gear when exiting a corner etc.
03-17-2009, 11:24 AM
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Originally Posted by mikeg3tsguap' post='819341' date='Mar 17 2009, 06:44 PM
If the rpms are to high the car wont let u downshift at all when its safe to downshift it will let u
03-17-2009, 11:50 AM
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Shift to accelerate, brake to slow down, in most cases. At the track or maintaining torque exiting a turn is another matter. Downshifting for sound effects at every stoplight will cause needless wear. Brakes are cheap, a new tranny isn't.
03-17-2009, 11:54 AM
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Originally Posted by CWS530' post='819384' date='Mar 17 2009, 12:50 PM
Shift to accelerate, brake to slow down, in most cases. At the track or maintaining torque exiting a turn is another matter. Downshifting for sound effects at every stoplight will cause needless wear. Brakes are cheap, a new tranny isn't.