Can these shifts harm an automatic transmission?

[69GTX]

Ran across some reading material over the past year or so that indicated some of my automatic transmission habits are wrong, and possibly harmful. Well, been doing them for over 40 yrs. The last 2 automatic transmissions I had went over 200K miles (older vehicles - a 1988 and 1997). But, being Bitog, I'm always looking for ways to fix any problems with how I operate/maintain my cars. Heck, I was driving 4 and 6 speed manual transmissions for over 20 yrs before I found out about rev matching, double clutch, etc.....go figure! Over the past 2 years I've read numerous articles/blogs on manual shifting and think I've worked out most of those kinks....and there were quite a few...lol.

Here's the list of what I think I do wrong in my automatic transmission. Many of these are centered around shifting into neutral before the car is fully stopped.

1. I'll often roll very slowly down the driveway in neutral with brake lightly applied, then slip it into "drive" as I roll into the clear street at approx 1-2 mph. (this is normal front end first decent)
2. When backing out of the driveway in "reverse," I'll often slip out of reverse into neutral a few seconds before I shift back to drive....coasting at approx 1-2 mph while I come to a stop. I do wait until the car is stopped before engaging "drive." Ideally I won't have to apply the brakes if I'm backing into a slight up-grade.
3. While stopped at longer lights where it may be 30 seconds or longer, I'll put it in "neutral" (or park), especially on hot summer days. Read somewhere where more heat is generated in the transmission while stopped in "drive" with brake applied.
4. While in "drive" at approx 40 mph and I want to speed up the shift to 3rd (for whatever reason and w/o losing speed), I have slapped it in neutral, rev matched to approx 2000 rpm, then shifted to "third." Most of those have felt pretty smooth. Don't do it often.

How many of 1,2,3,4 are just plain wrong/harmful? And if so, what part of the trans am I over-stressing? Or is it all of no consequence? Are there other common faults practiced by most drivers? Maybe I missed some of them?

Flame Away.

 

[69GTX]

Fwiw, back in the days of my coasting down long hills to conserve gas (15 yrs ago) I recall one occurrence where at approx 45-55 mph and starting to climb the next grade I did my shift from "neutral" to "drive." Well, I missed "drive." I somehow found "reverse" probably while being too occupied with what was on the radio. The car bucked a bit, came to a fairly abrupt halt/stalled. I was sure I destroyed the transmission. But, that was one tough '85 Ford LTD 6 cyl. It started fine and off I went. No issues with the transmission right until I sold it a couple years later. Had about 165K miles at that point and the engine had numerous issues and the body had numerous dents.

I sold that car to a young lad in my neighborhood for $50. I could have junked it for more. He was looking for cheap transportation to get him to California, 3000 miles away. I told him he'd be fortunate to make it out of the state. Never did find out how he made out.

 

[Dallas69]

Park
Reverse
Drive
That's all I've ever needed and mine have lasted a long time.
I think you are over thinking this.
They are called an automatic for a reason.

 

[RooflessVW]

Originally Posted By: Dallas69
Park
Reverse
Drive
That's all I've ever needed and mine have lasted a long time.
I think you are over thinking this.
They are called an automatic for a reason.

+1

If you want to speed up a shift up (or down), give it less or more gas. Don't take it out of gear and try to rev match.

Leave it in gear costing downhill.

 

[Rolla07]

I am not sure what harm that has but I dont know why you do those things. Why not reverse instead of neutral when going down ur driveway? I guess Im just not sure why you do those things when you can just use it normally the way it was intended.

 

[69GTX]

Originally Posted By: Dallas69
Park
I think you are over thinking this.
They are called an automatic for a reason.


Maybe so. Just listing what I've done for the past 40 yrs, never once thinking about it...until recently. I never thought too much about my manual trans shifting until 2 years ago. All those miles I down shifted to "slow" the car. Not realizing there was a better, safer, and more efficient way. Sometimes it helps to ask the dumb questions.

Here's one that will blow you away. I drove my automatic transmissions for 20 years without ever once realizing there was a kick-down shift feature from 4th to 3rd, or 4th to 2nd based on vacuum. I learned how to drive smoothly, safely, and efficiently. It wasn't until I had a panic situation in 1991/1992 where I "had" to floor the gas. The car shifted down to 2nd and off it went. I was stunned. That sparked my obsession with performance cars over the next 25 years. In 1992 I bought my first 4 speed '69 roadrunner. For those 1st 20 years my brother called me the "creeper" because I was so darn slow and methodical....idling into stop lights from 1/8th mile away.

 

[69GTX]

Originally Posted By: Rolla07
I am not sure what harm that has but I dont know why you do those things. Why not reverse instead of neutral when going down ur driveway? I guess Im just not sure why you do those things when you can just use it normally the way it was intended.


The car can be pointed either way in the driveway. If it's below the flat level on the slight grade, a slip into "neutral" will get it down just fine. Another thing I read a few years ago, was that putting your automatic trans in "reverse" the very first thing, is more stressful to it. Don't know if that's true. But, since I read it on line..... In any case I try to make the first shift into "drive" before using "reverse." My preference is to back the car in the drive way so "reverse" is not needed.

You have to move through "neutral" in all those situations. I think I started doing that stuff to avoid applying the brakes at all in those very low speed shifts...where I could utilize the grade of the road/driveway and/or the tire's friction to stop the car's motion while in neutral. As soon as the motion was stopped, shift into "drive." Same idea when avoiding the brakes when approaching stops. Never been one to want to speed up to lights and then jam on the brakes, especially when I know the local lights and how long they take. I think it all morphed into a driving style where brake avoidance, and less/light throttle was always better. I don't think about it when driving. My left foot used for braking is probably part of the same stuff too. I'll often have my left foot poised a fraction of an inch above the brake pedal as I'm throttling off a bit into tighter traffic. Or if need to get off a light first in tight traffic, left foot on brake and right foot just lightly in contact to the accelerator pedal waiting to strike.

 

[john6974332]

Originally Posted By: 69GTX
1. I'll often roll very slowly down the driveway in neutral with brake lightly applied, then slip it into "drive" as I roll into the clear street at approx 1-2 mph. (this is normal front end first decent)

x2 on this except I'm going faster than 2 mph. My car revs high (1500-1700 rpm) when first starting up cold, I don't like dropping it into drive at a complete standstill.

#4 I wouldn't feel comfortable doing in an automatic.

Interesting watch
https://www.youtube.com/watch?v=6zzEtxJkC7Y

 

[clinebarger]

I find all those practices odd, The only one I see causing an issue is #4 depending on the design of the transmission......

I'll use a GM 4L80E as an example.......
Putting it neutral at speed will cause all Clutch packs & Bands to release, In turn causing the Direct Drum to take the path of least resistance....Which means the Drum is now overrunning 3 times the RPM that the Output Shaft is turning. The shift back into 3rd will bring the Directs back on & they have to slow the Drum back down to drive shaft speed, This is particularly hard on the Direct Frictions because they have to slow down a 16 pound drum with inadequate/low Line Pressure.

Rev-matching the engine does nothing to help with the Line Pressure issue whether TV Cable, Vacuum Modulated, Or Solenoid controlled because your not loading the engine, TV & Solenoid will add some pressure from throttle input......But it takes little throttle to rev a engine to desired RPM in neutral.

If you need to pass/kick down a gear.....Force a Automatic Detent by gassing it, They're designed to work this way!

 

[69GTX]

Originally Posted By: john6974332
x2 on this except I'm going faster than 2 mph. My car revs high (1500-1700 rpm) when first starting up cold, I don't like dropping it into drive at a complete standstill.

#4 I wouldn't feel comfortable doing in an automatic.

Interesting watch
https://www.youtube.com/watch?v=6zzEtxJkC7Y


Thanks for that link. I don't violate that guy's rule #2 as I don't shift directly from D/R or R/D with the car in motion. I slip out of those gears into neutral for a bit. Then shift to D/R once stopped without usually applying the brakes, which is why I do it. I don't do #3 which is launching the vehicle with revs. I never rev it up and then drop into gear, in any car.

While I used to do his #1, I no longer really do it. I guess I could try an automatic kick-down from "D" to "3." But if you miss it by applying too little pedal, you'll end up going a lot faster than intended while still in "D"...or maybe end up in "2nd" if you mashed it too hard. Then you can slip it into "3" either way, letting the car do the downshift automatically.

Decent video. I've viewed that guy's videos on manual transmissions in year's past.

 

[69GTX]

Originally Posted By: clinebarger
If you need to pass/kick down a gear.....Force a Automatic Detent by gassing it, They're designed to work this way!


Thanks clinebarger. Will start trying to modify my ways on #4. When passing this is what we're trying to do, no doubt.

But, I'm going the other way, trying to slow down and/or get more traction/rpm. For example while descending a hill, or approaching a curve, etc. and you want it in from "D" to "3" now. I would think most people would just slam the shifter into "3" without thinking. Guess you could always apply the brakes and just slow to "3rd" speed then select "3". If people are right behind you, I'm not a big fan of the hard braking. But, I understand the concern now. I don't think most people are going to think through a "kick down" and then select "3" or "2"....they'll probably just jam on the brakes or move the shifter into "3" as soon as that thought pops into their heads.

My old 1970 Challenger R/T automatic had a slap stick shifter. No doubt people would say that shifting your automatic trans up like a manual is bad for it. Yet, that's what the Slap Stick allowed you to do. Was that causing unusual wear/stress vs. allowing regular factory shifts?

 

[Linctex]

Originally Posted By: 69GTX
1. I'll often roll very slowly down the driveway in neutral with brake lightly applied, then slip it into "drive" as I roll into the clear street at approx 1-2 mph. (this is normal front end first decent)
2. When backing out of the driveway in "reverse," I'll often slip out of reverse into neutral a few seconds before I shift back to drive....coasting at approx 1-2 mph while I come to a stop. I do wait until the car is stopped before engaging "drive." Ideally I won't have to apply the brakes if I'm backing into a slight up-grade.
3. While stopped at longer lights where it may be 30 seconds or longer, I'll put it in "neutral" (or park), especially on hot summer days. Read somewhere where more heat is generated in the transmission while stopped in "drive" with brake applied.


I can't see how it's possible to do any damage by doing these three. I've been shifting into neutral at stoplights since 1986 and have never had to rebuild an auto trans in my life.

 

[splinter]

Originally Posted By: 69GTX
..I "had" to floor the gas. The car shifted down to 2nd and off it went. I was stunned..

Live a little! Probably no harm done from your aforementioned automatic idiosyncrasies, either.

I'll sometimes 'rev-match' my automatics on downshifts with a quick throttle blip to ease loading on the clutches and frictions whist decelerating briskly.
Quite likely a holdover habit from heel and toe techniques on the weekend cars.

 

[69GTX]

Originally Posted By: splinter
Live a little! Probably no harm done from your aforementioned automatic idiosyncrasies, either.

I'll sometimes 'rev-match' my automatics on downshifts with a quick throttle blip to ease loading on the clutches and frictions whist decelerating briskly.
Quite likely a holdover habit from heel and toe techniques on the weekend cars.




Live a little? I hear you.

In my defense, I got burnt out from driving in my mid-20's driving lack luster slant 6 engined cars. I did 3 very long, near cross country trips in a 12 month period...without cruise control. And 2 of them were done in 3-4 days while driving 60-65 mph max. After that, I hated driving and couldn't mentally do anything more than 10-15 mile trips until about 10 years later. Cars were transportation to get from point A to B, and nothing more. I'd have taken a bus to work if it was convenient.

The above changed in 1991 when I started toying with the idea of a "fun" classic car with horsepower and bang for the buck. Turns out they were pretty cheap at that time. Went through about a dozen performance cars over the following 12 years, attending hundreds car shows/cruise nights. Funny that I almost settled on a stodgy looking, mid-1960's Ford with a 352 for my first car...not much different than the weak 6 bangers I was so used too. Luckily I passed on that and next got to see a "curious yellow" 1971 GTX with air grabber hood. I was now hooked on 1967-1971 muscle cars.

 

[Dallas69]

I guess I don't understand why you want to drive an automatic like a manual.
You are working too hard at it.

 

[69GTX]

Originally Posted By: Dallas69
I guess I don't understand why you want to drive an automatic like a manual.
You are working too hard at it.


There's no extra work involved. I do it without even thinking most of the time. Even the owners manual says that the lower 2 forward gears are there to be used at times...and to select them when you need them. So I do, especially using "3rd" for the first 2-3 miles for faster engine oil warmup. Anyone who shifts from "R" to "D" has to go through neutral to get there. I often do that with the car still moving at 1-2 mph in neutral. Once the car comes to a stop against the grade, I select "D" to move along. It's a very smooth and slow transition, usually w/o needing brakes. Though, I realize most people will barrel out of their driveways in "R" and then slam the brakes on at 5-10 mph or higher, shaking the car violently. No doubt they save a couple seconds over me. 95% of the time transmission automatically selects the gear for me. When I'm driving my manual 6 speed trans, I select the gears. Undoubtedly, a little of that T56 rubs off.


This site/article recommends shifting into neutral at extended stops to take the load off the trans, contrary to the video posted above.

Advanced Auto Transmission care

One plug for selecting neutral was on hot days where you are stuck in traffic for longer periods.

These guys say no to neutral 90% of the time

Canadian winter driver instructors suggest hard braking in neutral preferable to keeping it in gear

 

[69GTX]

These guys have taken "manual" automatic shifting to another level

 

[Linctex]

There is NO HARM EVER shifting to neutral when stopped.

It is the simple act of engaging and disengaging clutches internally.....
which is EXACTLY what happens every single time an auto trans shifts gears!

 

[RooflessVW]

Originally Posted By: Linctex
There is NO HARM EVER shifting to neutral when stopped.

It is the simple act of engaging and disengaging clutches internally.....
which is EXACTLY what happens every single time an auto trans shifts gears!

Well that's not true 100% of the time. If you shift the older ZF 4HP into neutral after it has been in drive and rev the engine (like during a California emissions test), you will burn the fluid and nuke the "A" pack.

 

[69GTX]

Originally Posted By: Linctex
There is NO HARM EVER shifting to neutral when stopped.

It is the simple act of engaging and disengaging clutches internally.....
which is EXACTLY what happens every single time an auto trans shifts gears!



How about shifting into neutral when going 1-2 mph? Doesn't seem like there would be much difference between this and fully stopped.