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  #1  
Old 09-07-2006, 01:47 AM
Frylock Frylock is offline
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Shifting into "Drive" while moving backward in an Automatic Transmission

Shifting into "drive" while moving backward in a car with automatic transmission is bad, isn't it?

Or not? Or does it depend on something(s) or other(s)?

-Kris
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  #2  
Old 09-07-2006, 02:13 AM
groman groman is offline
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Well, it's rough on the transmission if it agrees to do it. Some won't.
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  #3  
Old 09-07-2006, 02:23 AM
Frylock Frylock is offline
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Quote:
Originally Posted by groman
Well, it's rough on the transmission if it agrees to do it. Some won't.
I guess I'm not certain my car agrees to do it or not. You can put the shifter in "drive" position while the car is moving backwards, but maybe it's not actually shifting til the car has come to a stop?

I don't know for sure, because this isn't happening while I'm driving. I always thought this was a big "no-no" so I never do it. My wife, however, does it every single time she changes from reverse to drive. She insists there's nothing wrong with it.

Our last car would give a violent kick when she did this, but only the first time she did it on any particular day. I insisted she was damaging the car. She insisted it was just happening because the car wasn't warmed up yet, and she pointed out it jumped a little (though not as much!) even when she first came to a full and complete stop.

So anyway, now we have a new car, and I want to know once and for all whether she's causing damage when she does this or not. Though it looks like it depends on the car, based on your answer.

-FrL-
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  #4  
Old 09-07-2006, 05:08 AM
Rick Rick is offline
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While it may not hurt the trans (more on this in a minute) I can state with no fear of contradiction that under no conditions will doing this be helpful to the longevity of the trans.
Note: When used in the next paragraph the word brake refers to a planetary gear brake inside an automatic transmission, not the hydraulic wheel brakes.
On most automatic transmissions moving the shifter moves a valve inside the transmission called the manual valve. Put simply this valve directs fluid to the proper locations for P R N D etc. If the car is moving backward, fluid is being sent to some of the clutches, brakes and freewheels (AKA sprag clutches) inside the trans. Moving the shifter to D 3 2 or 1 will direct fluid to different clutches, brakes and freewheels. If you are still moving backward and you move the shifter the momentum of the car will be driving the innards of the trans one direction, and when D is engaged the engine will be trying to drive the innards of the trans the other. Inside the transmission the a clutch or a brake is going to wind up slipping at least a little bit until the rearward momentum is killed. Slippage causes wear and heat. Wear can cause bits of clutch lining to flake off which can cause problems or if enough material is shed, the clutch or the brake might / will start to slip and then it is trans repair time. Heat is what kills trans fluid, and bad fluid can also lead to transmission failure.
The shock on the driveline can also be very bad for engine / transmission mounts, drive shaft u-joints, CV joints etc.
But what about the may not hurt part? On some electronic transmissions there may be an electronic lockout that prevents the engagement of a gear if the car is moving. For example on the cars I teach on, if you are going over about 3 mph, and try and select reverse, the manual valve will move, but the electronic solenoids are not energized until the speed drops below 3 mph. There is a drive line shock at that speed. Also since the speedo does not know forward from reverse, the electronic prevention is only for reverse. If you are traveling backward, there is nothing to prevent you from selecting D at any speed and hurting things.
My suggestion is stop the car with the brakes, they are designed to do this job, and they are lots cheaper to repair than a transmission. Unless of course you want to be on your AAMCO dealers favorite customer list.
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  #5  
Old 09-07-2006, 06:39 AM
Lobelia Overhill Lobelia Overhill is offline
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Going by the racket the car makes I'd say it's not a good idea... (having done so accidently several times)
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  #6  
Old 09-07-2006, 07:03 AM
crazyjoe crazyjoe is offline
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My HS Auto shop teacher used to pull out this ugly, twisted hunk of metal several times throughout the school year. It was the drive shaft from a late 80s Pontiac Firebird GTA, twisted into pretzel l ike contortions because someone (a former student) was having fun doing "R to D slams" in a parking lot. He'd get the car going about 15 - 20mph in reverse and then slam it into Drive, allowing him to squeal the tires very nicely.

It was a brand new vehicle, and if one of the dealer mechanics hadn't been witnessing him doing it, he might have gotten it repaired under warranty. As it was, it was not a cheap repair.

So even if it's not too bad on the transmission, it can be over-stressful on other parts of the car. In fact, the entire driveline. I'd say don't do it.
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  #7  
Old 09-07-2006, 08:09 AM
Mr. Slant Mr.  Slant is offline
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What about downshifting to avoid overspeed while coasting down hills in town?
OD to D?
What about OD to 1?
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  #8  
Old 09-07-2006, 09:05 AM
crazyjoe crazyjoe is offline
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The general rule on downshifting and using engine breaking is that it does put wear on the transmission (both automatic and manual) and clutch, and that wheel brakes, which are much cheaper and easier to replace, should be used instead of downshifting as a general rule.

In cases where not downshifting would cause a potential braking failure, such as in mountain regions, etc, then you do what you need to do to be safe.

In most cars, going from OD to 1 won't actually shift it all the way down to 1st gear. Most transmissions are electronically controlled and won't shift down gears until a certain speed threshold is met (probably somewhere around 15mph for 1st gear, but it depends on the car). It will shift it into the lowest gear allowed by the electronic speed controls, so if you're going 45mph, it might shift into 3rd (or D, or whatever) or 2nd, but almost positively not 1st.
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  #9  
Old 09-07-2006, 09:25 AM
Gary T Gary T is offline
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Quote:
Originally Posted by Frylock
My wife, however, does it every single time she changes from reverse to drive. She insists there's nothing wrong with it.
She's been lucky so far. It's not true that there's nothing wrong with it. It is true that it usually doesn't result in sudden catastrophic failure, but that doesn't mean that it isn't shortening the life of the tranny.

Saying there's nothing wrong with doing this is like saying arsenic won't hurt you because you've eaten it several times and are still alive. Eat arsenic long enough and some morning you'll wake up dead. Abuse a transmission this way long enough and some morning you'll wake up to a hefty repair bill.
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  #10  
Old 09-07-2006, 02:46 PM
Rick Rick is offline
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Quote:
Originally Posted by Mr. Slant
What about downshifting to avoid overspeed while coasting down hills in town?
OD to D?
What about OD to 1?
I don't see this as much of a problem. all of the parts inside the transmission are traveling the same direction when you downshift. This is way different than going from R to D.
Downshifting is a really good idea on long steep grades, when using just brakes could lead to overheating and fade.
As far as OD to one goes, every auto trans I have ever seen limits as to how fast a lower gear can be selected. For example on one 4 speed auto (Just becasue these numbers stick in my head)
D (OD) to 3 at any speed
3rd to 2 (Or D to 2) @ a max of 74 MPH
2 to 1 @ a max of 33 mph
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  #11  
Old 09-07-2006, 03:12 PM
Mr. Slant Mr.  Slant is offline
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How about if I'm in town, and coasting to a stop light?
Or cruising down a little tiny hill?
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  #12  
Old 09-07-2006, 07:46 PM
commasense commasense is offline
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Quote:
Originally Posted by Mr. Slant
How about if I'm in town, and coasting to a stop light?
Or cruising down a little tiny hill?
No. In those circumstances, use the brakes. That's what they're there for.
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  #13  
Old 09-07-2006, 08:01 PM
bughunter bughunter is offline
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Quote:
Originally Posted by Mr. Slant
What about downshifting to avoid overspeed while coasting down hills in town?
OD to D?
What about OD to 1?
I use OD to D all the time in my Ford to go up hills or to downshift and overtake at freeway speeds. Provided I'm not too hard or too light on the throttle, it doesn't seem to cause too much stress on the drive train.

Or, more generally: If I'm causing excess wear on the car, it's my driving style in general.

Time for an anecdote:

My previous Ford had a similar transmission, and I'd use OD->D in order to slow the vehicle without my brake lights illuminating (and thus attracting attention from a highway patrolman). But I stopped doing that one morning when, bleary-eyed and still absorbing coffee, I attempted to shift out of overdrive --- and moved the lever the wrong direction, into Reverse.

Drive to Reverse at 80 MPH.

The car indeed slowed, quite rapidly. Even though I realized my error instantly, the tranny had about a half second to engage in reverse before I threw it into neutral. I cautiously engaged Drive again, and pressed the accelerator...

No effect.

So I coasted to a stop and got towed off the freeway by the service patrol. I called my boss and my girlfriend and explained I would be delayed due to car problems, then called the dealership and asked their advice. Then I called AAA for a tow to the garage.

On a whim, I got in the car and started it, and engaged Drive to see what would happen. It moved, and made no horrible noises! In fact, the only noticeable effect was that it took Reverse an extra half second longer to engage than it did before... as if the car was hesitant to comply with that operation again. I took it in for a ATF change and filter inspection to see if there was any debris or small parts in the filter, and found none.

I probably slammed a valve somewhere in the transmission or torque converter, and it just needed to cool down to recover.
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  #14  
Old 09-07-2006, 08:06 PM
bughunter bughunter is offline
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Quote:
Originally Posted by Rick
As far as OD to one goes, every auto trans I have ever seen limits as to how fast a lower gear can be selected. For example on one 4 speed auto (Just becasue these numbers stick in my head)
D (OD) to 3 at any speed
3rd to 2 (Or D to 2) @ a max of 74 MPH
2 to 1 @ a max of 33 mph
Yes, the owner's manual for one's particular vehicle will usually have those speeds listed for each of the model's available transmissions.
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  #15  
Old 09-07-2006, 08:32 PM
Rick Rick is offline
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Quote:
Originally Posted by Mr. Slant
How about if I'm in town, and coasting to a stop light?
Or cruising down a little tiny hill?
IMHO sifting down in those conditions is no different (as far as the trans is concerned) then if you were to press the accelerator to the floor and activate kick down at the same speed. Hell there might even be slightly less wear in the downsift than in a full throttle downshift due to the lack of engine torque being applied.
I don't see it as being a problem.
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  #16  
Old 09-07-2006, 09:24 PM
Monty Monty is offline
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Another anecdote: Shortly after getting my first driver license, while backing up I clipped the garage concrete stanchion with my dad's Chevy Nova. I panicked and slammed the gear lever into Park. The car wasn't too happy with that and I had to fight the lever a bit to get it out of Park.

Luckily for me, Dad called that "my one free accident repair." Luckily for dad, it was a cheap repair job for the doors.
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  #17  
Old 09-07-2006, 09:44 PM
kanicbird kanicbird is offline
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Quote:
Originally Posted by Rick
IMHO sifting down in those conditions is no different (as far as the trans is concerned) then if you were to press the accelerator to the floor and activate kick down at the same speed.
I have wondered about this. Perhaps it's the number of times a downshift at higher RPM's that add to the wear (and manually downshifting will add to the # of times), also I wondered how much extra wear when one manually downshifts to slow down when you are going to get into that gear anyway.
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  #18  
Old 09-07-2006, 11:33 PM
Rick Rick is offline
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Quote:
Originally Posted by kanicbird
I have wondered about this. Perhaps it's the number of times a downshift at higher RPM's that add to the wear (and manually downshifting will add to the # of times), also I wondered how much extra wear when one manually downshifts to slow down when you are going to get into that gear anyway.
OK anything you do to the transmission will cause wear. This includes starting the engine, putting it in gear, and stepping on the gas. The question is how much wear, and is that acceptable.
So how much additional wear is created when you downshift? IMHO not much. Since I know of no studies that have looked at this, all I can go by is my years of experience in the car business, and gut feeling.
My experience and gut tell me that downshifting the car every now and agin is not going to knock off a measureable amount miles off the life of the trans. In all my years of auto repair, I have never seen a trans failure that I could even remotly pin to the trans being downshifted. So I downshift if I am going down a hill, or if I am in the mood. If you feel diferent then don't downshift your automatic.
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  #19  
Old 09-08-2006, 12:00 AM
GusNSpot GusNSpot is offline
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At at known long stop lights, locked traffic, anything over about 30 seconds, if I am just sitter there, I move the tranny to netural. Makes me all happy and nice feeling and I'll leave all the reasoning to others.....
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  #20  
Old 09-08-2006, 12:01 AM
A.R. Cane A.R. Cane is offline
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I've downshifted a/t's for years w/o any problems. You do have to use some common sense and not overspeed the engine and/or tranny. It's not much different from downshifting a manual, but shifting into a fwd gear while the vehicle is rolling backwards, uh, uh, that's just not real smart.
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  #21  
Old 09-08-2006, 03:20 AM
Baffle Baffle is offline
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Quote:
Originally Posted by GusNSpot
At at known long stop lights, locked traffic, anything over about 30 seconds, if I am just sitter there, I move the tranny to netural. Makes me all happy and nice feeling and I'll leave all the reasoning to others.....
Hah, I see that and raise one better: If I think the light's going to be more than twenty seconds I turn off my engine altogether. Putting it in neutral at any stop is just par for the course with a manual transmission though.
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  #22  
Old 09-08-2006, 04:23 AM
Lobelia Overhill Lobelia Overhill is offline
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Can some confirm/deny something about automatic cars for me? When I accelerate occasionally the engine will "growl" - much like a manual does when you need to change gear - a driving instructor told me that's basically what the car is doing... my Da on the other hand says I'm burning out the engine [again*] and yells at me

*I have never damaged the engine of his precious car
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  #23  
Old 09-08-2006, 07:00 AM
Mr. Slant Mr.  Slant is offline
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Lobelia,

From your description, it sounds like your car is making the sound associated with reaching higher RPM.
The car in my driveway has an engine with an operating range of 650 to 6000 RPM.
If I accelerate steadily to speed, it will go from one gear to another at between 1500 and 2100 RPM.
If I use substantial throttle, the computer realizes I need more horsepower than I can get from low RPM, and it proceeds to let the engine achieve higher RPM to gain access to more power. That could mean upshifts would happen at 3000 to 4000 RPM.
Finally, if I floor the throttle, the engine and computer will attempt to give me as much power as possible. That means my upshifts happen around 5500 RPM.
At 2000 RPM my car doesn't sound very "revvy". Somewhere after 3000 it does sound like it's turning substantial RPM, and by 5000 RPM it is screaming.

If your car has been running for more than a few minutes and you're pushing it for more power, you'll be fine unless you're actually flooring the gas all the time.
If the guys who made your car thought that 4000 RPM would break it, *YOU WOULDN'T BE ABLE* to get to 4000 RPM.
If you are really interested in this let me know, I can dig up some good reading for you on this topic.
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  #24  
Old 09-08-2006, 02:22 PM
groman groman is offline
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Quote:
Originally Posted by Mr. Slant
If your car has been running for more than a few minutes and you're pushing it for more power, you'll be fine unless you're actually flooring the gas all the time.
I think this is generally true of smaller (or Japanese cars) but not big honking american cars. I've put probably 50K-70K miles on big americans with pedal to the floorboard and they're all purring along just nicely but the Honda, Toyota and the tiny Saturn all lasted about 10K-15K after I started driving them.
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  #25  
Old 09-08-2006, 02:32 PM
pulykamell pulykamell is online now
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Quote:
Originally Posted by GusNSpot
At at known long stop lights, locked traffic, anything over about 30 seconds, if I am just sitter there, I move the tranny to netural. Makes me all happy and nice feeling and I'll leave all the reasoning to others.....
Hmm...I am almost always in neutral if I'm at a full stop, long light or not--Ive' just been taught to never ride the clutch (or whatever the equivalent expression would be in this case). I was taught that even clutch fully-in at a stop, you're causing wear to your transmission. Is this not the case?
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  #26  
Old 09-08-2006, 03:11 PM
Asimovian Asimovian is online now
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*sigh*

Glad I read this thread. I will shamefully admit to following the practice of backing out of my driveway, throwing it into neutral for a bit while the car slows down, and then throwing it into drive while the car is still moving (albeit slowly) backwards. I actually do the same thing with our manual. I'm not sure when or why I developed the habit, but I think this thread will put an end to it.

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  #27  
Old 09-08-2006, 04:03 PM
groman groman is offline
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Quote:
Originally Posted by pulykamell
Hmm...I am almost always in neutral if I'm at a full stop, long light or not--Ive' just been taught to never ride the clutch (or whatever the equivalent expression would be in this case). I was taught that even clutch fully-in at a stop, you're causing wear to your transmission. Is this not the case?
I don't know, I think time causes wear to your transmission. If the clutch is fully in I do not believe anything in your transmission is moving, while if you are in neutral with the clutch out (I don't know why you would be) parts of your tranmission are moving. Right?
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  #28  
Old 09-08-2006, 05:02 PM
Rick Rick is offline
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Quote:
Originally Posted by pulykamell
Hmm...I am almost always in neutral if I'm at a full stop, long light or not--Ive' just been taught to never ride the clutch (or whatever the equivalent expression would be in this case). I was taught that even clutch fully-in at a stop, you're causing wear to your transmission. Is this not the case?
Transmission will experience no wear if you sit with your foot on the clutch at a stoplight.
Inside the clutch itself there is a bearing that does not rotate when your foot is off the clutch but turns at engine speed when your foot is on the clutch called the throwout bearing.
Back in the day British cars used a carbon block that wore against the clutch pressure plate. If left your foot on the clutch too much you could wear out the throwout bearing before the clutch itself was bad. This then required the removal of the engine or transmission to replace. The same labor as replacing he entire clutch assembly. So usually at this point the entire clutch was replaced.
Cars now a days use a ball bearing, or a roller bearing. I cannot recall the last time I heard of a throwout bearing going out before the rest of the clutch.
But if it makes you feel all warm and fuzzy, hey knock yourself out, you aren't hurting anything.
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  #29  
Old 09-08-2006, 05:43 PM
Mr. Slant Mr.  Slant is offline
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Quote:
Originally Posted by groman
I think this is generally true of smaller (or Japanese cars) but not big honking american cars. I've put probably 50K-70K miles on big americans with pedal to the floorboard and they're all purring along just nicely but the Honda, Toyota and the tiny Saturn all lasted about 10K-15K after I started driving them.
Thanks for sharing this.
A few questions!
What was the failure mode when these cars lasted 10-15K miles?
Tranny went out? Cooling failure? Etc?
Your big American cars... V8? V6?
The Honda and Toyota vehicles, were you running the base model 4-cylinders or the V6 models?

There is something to be said for a lower specific outfit.

I saw a formula for engine life that went something along the lines of:

Avg Operating Horsepower / Cubic Inches Engine Displacement * X = Engine Lifespan in Hours
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  #30  
Old 09-08-2006, 07:01 PM
pulykamell pulykamell is online now
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Quote:
Originally Posted by Rick
Transmission will experience no wear if you sit with your foot on the clutch at a stoplight.
Inside the clutch itself there is a bearing that does not rotate when your foot is off the clutch but turns at engine speed when your foot is on the clutch called the throwout bearing.
Back in the day British cars used a carbon block that wore against the clutch pressure plate. If left your foot on the clutch too much you could wear out the throwout bearing before the clutch itself was bad. This then required the removal of the engine or transmission to replace. The same labor as replacing he entire clutch assembly. So usually at this point the entire clutch was replaced.
Cars now a days use a ball bearing, or a roller bearing. I cannot recall the last time I heard of a throwout bearing going out before the rest of the clutch.
But if it makes you feel all warm and fuzzy, hey knock yourself out, you aren't hurting anything.
Funny enough, I learned to drive manual from a British guy, so maybe that's where he picked it up from. Good to know that I sit on my clutch without any worries.
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  #31  
Old 09-08-2006, 07:17 PM
groman groman is offline
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Quote:
Originally Posted by Mr. Slant
Thanks for sharing this.
A few questions!
What was the failure mode when these cars lasted 10-15K miles?
Tranny went out? Cooling failure? Etc?
Engine blowouts. The Toyota kept blowing gaskets and warping different heads. After two resurfaced heads and four blown gaskets I gave up and junked it. The Honda blew a head gasket and was not worth fixing. The Saturn (american, I know, but small, four cylinder and uses similar design methodology) broke a piston rod at 90Mph and wrecked the engine at a mere 108K Miles on the odometer.

These weren't 10-15K from the factory. These were 10-15K from the time I started driving them. All of the cars were fairly aged but roughly the same age(~60-90K miles).

Quote:
Originally Posted by Mr. Slant
Your big American cars... V8? V6?
A Jeep I6 and a Chrysler V6.


Quote:
Originally Posted by Mr. Slant
The Honda and Toyota vehicles, were you running the base model 4-cylinders or the V6 models?
4-cylinders

Quote:
Originally Posted by Mr. Slant
There is something to be said for a lower specific outfit.

I saw a formula for engine life that went something along the lines of:

Avg Operating Horsepower / Cubic Inches Engine Displacement * X = Engine Lifespan in Hours
A total WAG but I would go with

(Engine Age x Average Operating RPM x # of Cylinders)/ (Displacement) = Probability of Engine Failure

With each of those variables multiplied by some unknown constant.
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  #32  
Old 09-08-2006, 08:15 PM
snailboy snailboy is offline
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Shifting an automatic manually will wear it out more quickly. Perhaps not all of them, but at least some. I'm not sure of the details, but if I remember correctly, shifting manually causes more hydraulic pressure than normal resulting in a rough shift. It has been said time and again by the experts in my car club that if you want to shift manually, you need to either get a manual valvebody (which is designed for manual shifts, I have one in one of my cars) or a manual transmission (I have one in the other car). An exception to this is disabling overdrive in a vehicle with an electronic transmission. That tells the computer, rather than the transmission, to downshift, so it actually happens just like it would if it downshifted automatically. It can cause wear on the engine and rest of the drivetrain if done at high speed though, so don't get crazy with it.

That said, it's not like it's going to grenade your transmission the third or fourth time you shift manually. If you need to do it, then do it. Just don't do it all the time. The manufacturers wouldn't have put that shifter there if you couldn't use it. But if you just want to use it for fun on a frequent basis, get a manual valvebody.
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  #33  
Old 09-08-2006, 08:31 PM
snailboy snailboy is offline
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I may have spoken too generally. Here's an article by one of the engineers that designed the Ford AOD-E and 4R70W transmissions. It answers this question (for these specific transmissions) in chapter 6.

Quote:
Will manual shifting hurt my transmission?
Well the answer is it depends. On any 1996 and newer 4R70W, you can do all the manual 1-2 and 2-1 shifts you want and not hurt anything. If it were older than a 1996, I'd shy away from manual 1-2's unless you've modified the main control. I would stay away from excessive manual 4-2's on all transmissions older than 1998. In 1998 the manual valve changed to allow the direct clutch to exhaust faster, resulting in less wear.
My car is a 1994, so I learned not to shift manually. I guess it depends on how well the transmission was designed.
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  #34  
Old 09-08-2006, 08:45 PM
Rick Rick is offline
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I am afraid I am going to need a much better cite than what you heard from the "experts" in your car club before I will believe that.
In a strictly hydraulic transmission, shifts are governed by throttle pressure, and governor pressure. When governor pressure overcomes throttle pressure the trans shifts up, when the reverse happens it shifts down. The shift itself is controlled by the transmission line pressure. If you manually select a gear, and then move the shifter, you are taking the governor pressure / throttle pressure out of the equation. The shift is still controlled by transmission line pressure with is constant.
In an electronically controlled transmission the computer controls all the shifts. No governor or throttle pressure. So on an electronically controlled trans it is the TCM / PCM controlling the shift solenoids. Line pressure in an electronically controlled trans can vary via a pressure control solenoid, and the computer determines the correct pressure under various conditions.

The only exception I can think of to this is the GM trubo 400 behind a Jag V-12. If you left it in first gear and floored it when the engine passed red line the transmission would shift into 2nd gear and burn the tires.
Probably not healthy for the trans, but very impressive to have the rear tires burn at 70MPH.

groman If you kept blowing 4 cylinder Toyota head gaskets, either you had defective machine work being done, or a incompetent mechanic. There is no reason that that engine should have kept blowing head gaskets.
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  #35  
Old 09-08-2006, 09:03 PM
Mr. Slant Mr.  Slant is offline
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Quote:
Originally Posted by groman
SNIP

A Jeep I6 and a Chrysler V6.


SNIP

A total WAG but I would go with

(Engine Age x Average Operating RPM x # of Cylinders)/ (Displacement) = Probability of Engine Failure

With each of those variables multiplied by some unknown constant.
Hmmmmm.
Very interesting info on those failures. Thank you!
As an aside, the 4.0 Liter Jeep I6 is bigger than some small V8 engines and has a reputation as an UNSINKABLE piece of machinery.
The Chrysler V6 engines I don't really know too much about by reputation.
If I didn't know better, I'd say you killed your small vehicles by simply exceeding the limits of their cooling systems, what with the blown gaskets and all.
On your formula I should point out that we answered two different questions... I spoke to engine lifespan, you spoke to likelihood of failure.
Incidentally, I suspect that you could save much time by representing horsepower with gallons of fuel burned, as so:

Gallons Per Hour Consumed / Cubic Inches Engine Displacement * X = Engine Lifespan in Hours
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  #36  
Old 09-08-2006, 09:42 PM
snailboy snailboy is offline
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Quote:
Originally Posted by Rick
I am afraid I am going to need a much better cite than what you heard from the "experts" in your car club before I will believe that.
If you won't trust someone who designs transmissions, I don't know what better cite I could provide.
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  #37  
Old 09-09-2006, 04:19 PM
Rick Rick is offline
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Posts: 15,701
snailboy you last post wasn't there when I started writing.
I will run this by some of the Ford tech specialists that I know and get their look on this.
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  #38  
Old 09-09-2006, 10:02 PM
snailboy snailboy is offline
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Quote:
Originally Posted by Rick
snailboy you last post wasn't there when I started writing.
Yeah, I thought about that after I made my post.

Quote:
I will run this by some of the Ford tech specialists that I know and get their look on this.
As you wish. The article was written by Jerry Wroblewski. I'm sure you can confirm with them that he is one of the designers of the AOD-E and 4R70W transmissions. Again, I'm not saying all transmissions have these problems, just some, including the earlier models of the above transmissions. They were trash. I know. I have one.
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