CarForum.net - Car Forums, Automotive News and Community
Home Gallery Register Calendar Members List

Go Back   CarForum.net - Car Forums, Automotive News and Community > Car Parts and Maintenance > Transmissions and Drivetrain

Reply
LinkBack Thread Tools
Unread 10-27-2009, 12:17 AM   #1
New Member
 
Join Date: Oct 2009
Posts: 5
Rep: 10 blackhawk777 is on a distinguished road
Default shifting gears while in motion

this question is for auto transmissions...

ive seen a lot of people do this without damaging anything yet people still say it shouldnt be done.

Shifting from R to D while still moving backwards at a SLOW speed, 2-4 mph aka 4-8km/h (ive seen a few people doing it at 7-11km/h)

here are the car specs and situation when this type of shifting was happening..

2001 Toyota Corolla with 200000km
shifting from R to D at 5-8 km/h
person has been doing this for all of the 200000km that he owned the car. no repairs needed so far.

2003 Ford Crown Vic Police Interceptor (real police car, real police officer)
with a Heavy Duty transmission
Shifted from R to D at around 8-13km/h
..to be honest i dont remember the cop ever touching the brakes.
Vehicle repair history: None

so can someone tell me why people keep condemning this type of behavior yet i have seen no proof that doing this will damage your transmission?

blackhawk777 is offline  
Reply With Quote
Unread 10-27-2009, 12:52 AM   #2
Spah sappin' mah susp!
 
Kenny McCormick's Avatar
 
Join Date: Jan 2009
Location: Earth...I think
Posts: 3,283
Rep: 96 Kenny McCormick will become famous soon enough
Default

Doing that will stress the shifting bands, planetaries and flexplate tremendously. If enough throttle is applied, you could outright shatter something(Usually the flexplate). With the front-drive, and especially considering the mileage on it, you can also snap axles at the joints.


The cop has a decent reason to do it, tho. He may be in a pursuit at the time, and any time spent coming to a stop means the perp is getting that much farther away.


Even if it doesn't outright break something, it will speed up the wear of the bands and clutches inside the automatic, and it will speed the wear of the other driveline components.
__________________
Tired Iron ain't got no time to wear out...

My rigs:

1985 Ford F150 | 4x2 | 300ci OHV inline six | 4-speed OD manual | 310K | No power brakes | Running 100% - It hasn't driven this good in 15 years!

1984 Ford F150 | 4x2 | 300ci six | granny four | 3.55 rear end | 210K | Brakes shot. Rear drums are doing most of the work. Not fit to drive due to that.
1997 Ford Explorer XLT | 4.0L Vulcan V6 | 5-speed automatic | shift-on-the-fly 4WD | 210,000 miles | Running 95% - Needs brakes on all four corners + bald tires
1989 Ford F150 | 300cid six...again | 5-speed | 4x4 | 160K | Needs brakes done as well. Oi!

Last edited by Kenny McCormick; 10-27-2009 at 01:10 AM.

Kenny McCormick is offline  
Reply With Quote
Unread 10-27-2009, 07:30 PM   #3
Community Director
 
Mike's Avatar
 
Join Date: Jun 2008
Location: Between a rock and a hard place.
Posts: 7,089
Rep: 144 Mike will become famous soon enoughMike will become famous soon enough
Default

Basically my stance is that it's not necessarily great for it but it's not a big deal if you do it; i can't see it hurting much unless you're moving at a decent pace.
__________________
"He shouted: 'You've won! Didn't you know?' I didn't, and it's about the nicest thing I've ever been told" -Bruce McLaren, 1968 Belgian Grand Prix
Read the rules! | DO NOT REPLY TO SPAM
Daily Driver: 1996 Chevy Blazer LT 4x4 - 235k miles
Girlfriend's Car: 2003 Oldsmobile Alero GLS 3.4L 4 door - 160k miles
Bikes: 1979 Yamaha XS 750, 1981 Yamaha XS 400
Plow Truck: 2002 Chevy Silverado 1500 - 150k miles [5.3L, 4x4, ECSB, Eaton Rear Locker]
Others: 2012 Chevy Cruze automatic, Sonic sedan manual, both 1.4 Turbo, LT trim


Mike is offline Mike's Gallery  
Reply With Quote
Unread 10-27-2009, 07:34 PM   #4
Hammond Hand Luggage
 
cluffenstein's Avatar
 
Join Date: Jan 2007
Location: Chicago IL
Posts: 2,683
Rep: 60 cluffenstein will become famous soon enough
Default

I did it all the time in my old car, had some nice burnouts.. Don't do it in my new one.

Even doing it a lot my trans was still in tip top shape.
__________________
Quote:
Originally Posted by TestEcull
He may have ruined his cylinder walls and compression wings.
Quote:
Originally Posted by wierdo124
Yeah. Should hold up fine, long as you don't drive like a primate.

cluffenstein is offline cluffenstein's Gallery  
Reply With Quote
Unread 10-27-2009, 08:46 PM   #5
Stickers add HP brah
 
TwIsTeDbOi's Avatar
 
Join Date: Jun 2008
Location: Lakewood, IL
Posts: 1,257
Rep: 39 TwIsTeDbOi is on a distinguished road
Default

I've noticed both my dad's '96 Silverado and my '99 Grand Prix, when we go from R to D, the vehicle slows down enough to the point where the shift doesn't seem like it's stressing anything. I mean yeah if you're doing it at 5+ MPH it can be detrimental, but slower than 2-3MPH? I think it's fine.

I think I got it from him because he ALWAYS does it. Then again he's had a manual in every car/truck he's had up until he got that truck in '96.
__________________
Quote:
You can't compare German cars to Japanese cars. That's like comparing apples to herpes.
Cheap. Reliable. Fast. In the car world, you can only choose two of those.
1999 Jeep Cherokee XJ: Sagging rear leafs, 261,000mi
2006 GTO A4: Gone and not missed
2012 Mustang GT/CS 5.0/M6: FRPP 1.5" drop



Last edited by TwIsTeDbOi; 10-27-2009 at 08:55 PM.

TwIsTeDbOi is offline  
Reply With Quote
Unread 10-27-2009, 08:49 PM   #6
Retired Staff
 
Retrospekt's Avatar
 
Join Date: Jul 2006
Location: Chicago, IL
Posts: 601
Rep: 67 Retrospekt will become famous soon enough
Default

I go from R to D while moving sometimes..but we're talking 2mph max. I would NEVER shift while driving any faster.

Also, I've heard a lot of people say that even shifting from D to N while moving at higher speeds is very bad for the transmission.

Edit: I should mention that the reason I'm so terribly careful with my transmission is that it's an original automatic tranny from a 96 Camry with 150k miles. They're notorious for failing around this mileage, and I am not about to replace a transmission.
__________________
Family Cars: (Bold is mine).

1998 Nissan 200sx SE | i4 1.6L | 83,000 miles | Green | Running 100% |

1996 Nissan Sentra | i4 1.6L | 122,000 miles |Black |
2001 Nissan Maxima | V6 3.0L | 94,000 miles | Black |
2010 Toyota Camry | i4 2.5L | 5,500 miles | Silver |
1993 Toyota MR2 | 2.0L i4 560HP | 26psi Boost | Unknown Mileage | White| Scary to drive

Last edited by Retrospekt; 10-27-2009 at 09:02 PM.

Retrospekt is offline  
Reply With Quote
Unread 10-27-2009, 09:01 PM   #7
Community Director
 
Mike's Avatar
 
Join Date: Jun 2008
Location: Between a rock and a hard place.
Posts: 7,089
Rep: 144 Mike will become famous soon enoughMike will become famous soon enough
Default

Quote:
Originally Posted by Retrospekt View Post
Also, I've heard a lot of people say that even shifting from D to N while moving at higher speeds is very bad for the transmission.
Never heard that.
__________________
"He shouted: 'You've won! Didn't you know?' I didn't, and it's about the nicest thing I've ever been told" -Bruce McLaren, 1968 Belgian Grand Prix
Read the rules! | DO NOT REPLY TO SPAM
Daily Driver: 1996 Chevy Blazer LT 4x4 - 235k miles
Girlfriend's Car: 2003 Oldsmobile Alero GLS 3.4L 4 door - 160k miles
Bikes: 1979 Yamaha XS 750, 1981 Yamaha XS 400
Plow Truck: 2002 Chevy Silverado 1500 - 150k miles [5.3L, 4x4, ECSB, Eaton Rear Locker]
Others: 2012 Chevy Cruze automatic, Sonic sedan manual, both 1.4 Turbo, LT trim


Mike is offline Mike's Gallery  
Reply With Quote
Unread 10-27-2009, 11:04 PM   #8
Stickers add HP brah
 
TwIsTeDbOi's Avatar
 
Join Date: Jun 2008
Location: Lakewood, IL
Posts: 1,257
Rep: 39 TwIsTeDbOi is on a distinguished road
Default

I think it's just a lot of rumor and hearsay because automatics really have never been as reliable as manuals up until the recent years. That's just me though. But then again my sister would probably be the one to say stuff like this and then call me one day saying a mechanic is telling her her "muffler bearing" and "taillight gasket" are failing.
__________________
Quote:
You can't compare German cars to Japanese cars. That's like comparing apples to herpes.
Cheap. Reliable. Fast. In the car world, you can only choose two of those.
1999 Jeep Cherokee XJ: Sagging rear leafs, 261,000mi
2006 GTO A4: Gone and not missed
2012 Mustang GT/CS 5.0/M6: FRPP 1.5" drop



TwIsTeDbOi is offline  
Reply With Quote
Unread 10-28-2009, 12:48 AM   #9
Hammond Hand Luggage
 
cluffenstein's Avatar
 
Join Date: Jan 2007
Location: Chicago IL
Posts: 2,683
Rep: 60 cluffenstein will become famous soon enough
Default

LOL. but my 3rd brake light does have a gasket.. the only thing making it water tight!
__________________
Quote:
Originally Posted by TestEcull
He may have ruined his cylinder walls and compression wings.
Quote:
Originally Posted by wierdo124
Yeah. Should hold up fine, long as you don't drive like a primate.

cluffenstein is offline cluffenstein's Gallery  
Reply With Quote
Unread 10-28-2009, 01:28 AM   #10
Veteran Member
 
Join Date: Dec 2006
Location: Dallas, OR
Posts: 2,879
Rep: 38 KSIMP88 is on a distinguished road
Default

Quote:
Originally Posted by TestECull View Post
Doing that will stress the shifting bands, planetaries and flexplate tremendously. If enough throttle is applied, you could outright shatter something(Usually the flexplate). With the front-drive, and especially considering the mileage on it, you can also snap axles at the joints.


The cop has a decent reason to do it, tho. He may be in a pursuit at the time, and any time spent coming to a stop means the perp is getting that much farther away.


Even if it doesn't outright break something, it will speed up the wear of the bands and clutches inside the automatic, and it will speed the wear of the other driveline components.
All new Police Interceptors and Dodge Charger Pursuit Rated, and all other pursuit cars have a mechanism that forces the car to wait until speed is 0, before it transitions to D from R, or vice-versa. They will get you either way.
__________________
2001 Tahoe LT Autoride w/ third seat
K&N air filter

KSIMP88 is offline KSIMP88's Gallery  
Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 06:06 AM.

Shogun Interactive Development Copyright 2012 Shogun Interactive Development. All rights reserved.