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Old 07-14-2009, 07:00 PM   #21 (permalink)
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... which is normal (pull from N to D for column shift). The potential hazard there is if you shift from N into a forward gear that's too low for your current road speed.

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Old 07-14-2009, 07:02 PM   #22 (permalink)
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My Escort's shifter reads P-R-N-OD-D-L. One time I had shifted into D for engine braking and forgot to put it back into OD. I was approaching a hill at a little over 40 mph and wanted to bump the trans out of OD so I pulled the shifter down a notch, not realizing it was already in D. Remember there's no 2 on the shifter so it went straight for first gear, which redlines at 38 mph. Some cars will simply not engage a gear if it will over-rev the engine, but apparently my Escort doesn't have this feature. I felt the trans reach for first gear and felt the car start to lurch, and I realized what happened and bumped the shifter back before the engine zinged right past the redline. I've forgotten to put the shifter back to OD from D many times but that's the only time I've ever done that.

In a related story, a manual equipped car is in the works.
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Old 07-14-2009, 07:05 PM   #23 (permalink)
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Quote:
Originally Posted by MetroMPG View Post
... which is normal (pull from N to D for column shift). The potential hazard there is if you shift from N into a forward gear that's too low for your current road speed.
Modern cars won't downshift if it will overrev the engine. You can, however, throw the drive wheels into a skid if it downshifts at very high RPM and you're on icy or wet roads.
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Old 07-14-2009, 07:33 PM   #24 (permalink)
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Chrysler hydraulic transmissions won't (that I know of) engage first gear at anything over a certain speed, since the gear is equipped with a "sprag" clutch, which allows it to freewheel any time there is no force on the input shaft.
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Old 07-14-2009, 10:31 PM   #25 (permalink)
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Hello -

Maybe dumb thing to say, but this safety feature ONLY applies to modern automatics, right? Manuals can still self-destruct at the whim of the driver, yes?

I'm asking because I "like" to think of reverse as my last best hope for stopping in a situation where my brakes have failed. No tranny left, but won't fly over a cliff either.

CarloSW2
My Subaru, my Honda, and other 5MTs I've driven, have an interlock. As you're rowing through the gears, it won't let you go from 5th directly to R. You have to go 5, N (center the stick), R. And yeah, it'll let you spin the engine backwards if you really want to, or spin the engine at 20000 RPM until it grenades, or both. But no, there's no point in engine braking like that. Engine braking in forward gears works very well as long as you're going faster than idle. Slower than that, I suppose you could shift into R, give it throttle, and feather the clutch. No damage done to the tranny or engine.

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