3/4 of a Century and still the problem

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ClutchFork
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3/4 of a Century and still the problem

Post by ClutchFork »

Of automatic transmissions wanting to go when the car is in a stopped position. You'd have thought they would have solved it by not. We do have a pseudo-solution in the cars that shut the engine off at a stop, but that is a rather awkward solution that was not meant to treat the specific problem of transmission creep. You'd have thought with the advent of electronic tranmission controls several decades ago, they would have addressed the problem of creep. Hmmmm, maybe customers would have complained because they were accustomed to using transmission creep and a sort of hill holder feature.

Interesting article on Transmission Creep:
http://www.sixbullets.com/automatic%20t ... 0creep.htm
Stick shiftin since '77
theholycow wrote:Why in the world would you even want to be as smooth as an automatic? Might as well just drive an automatic...
IMBoring25
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Re: 3/4 of a Century and still the problem

Post by IMBoring25 »

Our newsed MDX has a Brake Hold function that you can activate that, any time you're at a stop and heavy enough on the brakes, leaves the service brakes applied until you reach critical mass on the throttle.

It's kind of a game having both systems active. I usually finish up a stop lightly enough on the brakes that stop/start doesn't trigger. If it looks like a long enough stop that it will be beneficial I just dip into the brakes a little more to activate both systems and then take feet completely off the pedals. Approaching ready to start, I try to kill the stop/start with a little throttle so I don't hold up traffic, then hold the throttle just shy of what kills the brake hold, then tip in that little extra throttle when I can actually go.

Also, some EVs can be one-pedal driven in their high-regeneration modes.
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Re: 3/4 of a Century and still the problem

Post by Rope-Pusher »

In days of yore, when carburetors utilized an idle-stop solenoid, I rigged a switch to disrupt power to said solenoid ("Solenoid" - there, I said it. Are you happy?) while the engine was still running. It lowered the idle speed to the point that the vehicle would no longer creep forward when in Drive.
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IMBoring25
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Re: 3/4 of a Century and still the problem

Post by IMBoring25 »

For that matter, in the conditions in which an automatic will creep, a manual will roll whichever way the hill slopes, and I'm not sure that's really a preferable condition.

I have been known to apply the parking brake at a long light, but the brake hold function is preferable in that it leaves the brake lights illuminated.

The blame really lies with the drivers unworthy of the term.
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potownrob
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Re: 3/4 of a Century and still the problem

Post by potownrob »

i don't see the problem with automatic creep; if anything, i like it. nothing quite like rolling through slow but steady traffic without touching the pedals.
ClutchFork wrote:...So I started carrying a stick of firewood with me and that became my parking brake.
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Re: 3/4 of a Century and still the problem

Post by Rope-Pusher »

Saw this discussion of the 2nd gen 8-speed slush-box on Allpar:

"Creep torque has been cut by fully opening a clutch during deceleration and when the vehicle is stopped, so that drivers don’t have to brake to keep the car from moving. The oil pump pressure has been cut in pressure by around 30%."
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
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ClutchFork
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Re: 3/4 of a Century and still the problem

Post by ClutchFork »

A high stall torque converter would also get rid of stoplight creep, no? It also helps you to peel out when the light turns green.
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theholycow wrote:Why in the world would you even want to be as smooth as an automatic? Might as well just drive an automatic...
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Re: 3/4 of a Century and still the problem

Post by Rope-Pusher »

ClutchFork wrote: Sun Feb 16, 2020 12:52 am A high stall torque converter would also get rid of stoplight creep, no? It also helps you to peel out when the light turns green.
Image
No, that creep will still be in the lane next to you at the stoplight, trying to get ahead of you before his lane ends, no matter what torque converter you use, but you should be able to blow his doors off when the light turns green if you have a high stall torque converter and react quickly to the signal.
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
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