Is it bad to let car automatically downshift for you?

j2dad5389 · 02-03-2020, 01:48 PM

Probably a dumb question, but it doesn't hurt to ask. Been using the paddles lately and it's so much fun revving up to 6k then upshifting, But when approaching red lights or stops, lately I've been letting the car do it automatically for me instead of manually downshifting. This shouldn't be an issue for the car, should it?

MassNerd · 02-03-2020, 05:04 PM

Not an issue. But downshifting is lots of fun too. Especially with the burbles!

jarhead3121 · 02-04-2020, 01:01 PM

I think it's there for safety reasons.. I honestly wish it didn't do that, but understand why it does it. Should be no harm..

cooolone2 · 02-04-2020, 01:22 PM

Anything the DME does will not hurt... The only error that can be introduced is "user" error! Lol

Careful with those high rev shifts

RoundelM3 · 02-13-2020, 10:55 AM

I guess I don't understand the question...why would any built-in functionality of the transmission be "an issue"?

gosi · 02-13-2020, 02:56 PM

Just because something is built in or allowed by the trans ECU, doesn’t mean it isn’t bad your transmission.

There are many edge cases and special features that do reduce transmission life. Launch control is the most obvious one. I’d hazard a guess and say that sport+ shifting with its agressive shifts is also not-the-best...

The car also lets you redline it 1 second after start up and shut it off after WOT. So what’s your point?

But OP letting the trans downshift for you won’t do any damage or wear your transmission...

Maynard · 02-15-2020, 03:21 PM

And IIRC, those faster sport+ shifts are actually kinder to the trans, less time slipping between gears. I think it will hold gear and not upshift at redline if you put it into full TCS off mode - it will always downshift as speed drops too low.

gosi · 02-16-2020, 07:33 AM

Quote:

Originally Posted by Maynard

And IIRC, those faster sport+ shifts are actually kinder to the trans, less time slipping between gears. I think it will hold gear and not upshift at redline if you put it into full TCS off mode - it will always downshift as speed drops too low.

Interesting point. I’m pretty sure that Sport+ will also hold gear at redline.

MetalMK · 02-21-2020, 10:09 PM

Quote:

Originally Posted by Maynard

And IIRC, those faster sport+ shifts are actually kinder to the trans, less time slipping between gears. I think it will hold gear and not upshift at redline if you put it into full TCS off mode - it will always downshift as speed drops too low.

That is true, if and only if you have a clutch. Does not matter for torque converter automatics like ZF8.

02-03-2020, 01:48 PM	#1
j2dad5389 Lieutenant 372 Rep 561 Posts Drives: 2020 M340i Join Date: Jul 2019 Location: Austin, TX iTrader: (0)	Is it bad to let car automatically downshift for you? Probably a dumb question, but it doesn't hurt to ask. Been using the paddles lately and it's so much fun revving up to 6k then upshifting, But when approaching red lights or stops, lately I've been letting the car do it automatically for me instead of manually downshifting. This shouldn't be an issue for the car, should it?
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02-03-2020, 05:04 PM	#2
MassNerd Second Lieutenant 171 Rep 294 Posts Drives: 2019 M240i Coupe RWD Join Date: Feb 2019 Location: New England iTrader: (0) Garage List 2019 BMW M240i coup ... [0.00]	Not an issue. But downshifting is lots of fun too. Especially with the burbles!
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02-04-2020, 01:01 PM	#3
jarhead3121 New Member 8 Rep 16 Posts Drives: 2019 M240 Convertible Join Date: Jan 2020 Location: Kentucky iTrader: (0)	I think it's there for safety reasons.. I honestly wish it didn't do that, but understand why it does it. Should be no harm.. __________________ -------------- 2019 M240 xDrive Vert 2018 Maserati GranTurismo MC Vert 2013 GMC Yukon XL 2004 Mercedes CLK 500
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02-04-2020, 01:22 PM	#4
cooolone2 Captain 625 Rep 706 Posts Drives: 20' M240iX B58, 01' 330XI E46 Join Date: Jul 2019 Location: NY, USA iTrader: (0)	Anything the DME does will not hurt... The only error that can be introduced is "user" error! Lol Careful with those high rev shifts
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02-13-2020, 10:55 AM	#5
RoundelM3 Major General 1834 Rep 6,989 Posts Drives: 15 F80 M3, 22 G01 X3 30i Join Date: Apr 2010 Location: Clayton, NC iTrader: (2) Garage List 2022 BMW X3 [9.83] 2015 BMW M3 [6.50]	I guess I don't understand the question...why would any built-in functionality of the transmission be "an issue"? __________________ 2015 F80 ///M3 Sedan 7DCT Tanzanite, 2022 X3 sDrive30i 8AT Brooklyn Grey
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02-13-2020, 02:56 PM	#6
gosi Private First Class 96 Rep 147 Posts Drives: M240 Join Date: Nov 2019 Location: Slovenia iTrader: (0)	Just because something is built in or allowed by the trans ECU, doesn’t mean it isn’t bad your transmission. There are many edge cases and special features that do reduce transmission life. Launch control is the most obvious one. I’d hazard a guess and say that sport+ shifting with its agressive shifts is also not-the-best... The car also lets you redline it 1 second after start up and shut it off after WOT. So what’s your point? But OP letting the trans downshift for you won’t do any damage or wear your transmission...
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02-15-2020, 03:21 PM	#7
Maynard Colonel 3847 Rep 2,872 Posts Drives: 228iX & M2C Join Date: Mar 2016 Location: Upstate NY iTrader: (1)	And IIRC, those faster sport+ shifts are actually kinder to the trans, less time slipping between gears. I think it will hold gear and not upshift at redline if you put it into full TCS off mode - it will always downshift as speed drops too low.
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