Automatic Owners - Do You Use 1st & 2nd?

[GCorvette]

I've recently had a couple of interesting conversations with C3 owners who amazed me when they said they never use 1st & 2nd and just use the Drive / 3rd on their automatics.

It has me wondering why and do many owners only use the 3rd / Drive option?

 

[Roscobbc]

Ask a late model automatic driver the same question (even with 4, 5, 6, 8 or even 10 ratios plus 'floppy' paddles and even a 'sport' button and I'm sure you'll get a similar response. The 'canny' auto driver will 'drive' with his or her right foot and know instinctively the best throttle position for the speed and redponse desired. Much the same with late model cars except driver will select 'sport' button as required. All in my opinion of course.....

 

[Oneball]

The only time I regularly stick an auto in low gear is going down hills. I’m still of the save the brakes mentality.

 

[Chuffer]

The only time I regularly stick an auto in low gear is going down hills. I’m still of the save the brakes mentality.

I thought it risks over heating the auto trans doing that .

I've recently had a couple of interesting conversations with C3 owners who amazed me when they said they never use 1st & 2nd and just use the Drive / 3rd on their automatics.

It has me wondering why and do many owners only use the 3rd / Drive option?

I am up and down from 3rd ( Drive) to 2nd as a matter of routine . Gives sharper acceleration and better throttle control when cornering . I have an Edelbrock Torker 2 single plain manifold so it thrives on keeping the revs up . Hardley ever manualy select 1st though as don`t like scream the revs to the red zone .

 

[Nassau65]

I put it in D, and away I go. That’s what auto boxes were built for.

 

[Oneball]

I thought it risks over heating the auto trans doing that .

Maybe if you’re coming down some pass in Colorado but in Worcestershire it’s not something you do for very long. Better than cooking the brakes.

 

[teamzr1]

As the auto tranny has been designed more and more complex, so has GM's ability to control the driver
and the output from engine to rear end

Problem with always just putting it in drive is the auto tranny has its own controller, today it has over 4 meg bytes of calibration control
IF never using other gears then the TCM (controller) learns the driver's style and adjust just for that style
That means that if seldom manually shifting the TCM has not learned that and the car is a pig when it needs more output

Here is an example of a C7 with auto tranny as the engine and tranny being controlled as how much torque is allowed, and when

Here is just one of the several torque tables in the tune, as you see depending on the RPM how much torque the TCM will allow as output
As you see if using D only and that also means lower RPMS then less torque will be allowed so good reason to downshift,
raise the load, torques up the drivetrain and allow as much as 100 ft/lbs more torque

Consider if driving up hill and having to push the mass yet TCM only allowing 2/3rds of the torque, add setting the Corvette into touring mode
and it's a slug in D only
Reason Corvette has had auto tranny paddle shifters as even GM knows using D only sucks and is boring

 

[teamzr1]

Maybe if you’re coming down some pass in Colorado but in Worcestershire it’s not something you do for very long. Better than cooking the brakes.

Reminds me when being at the top of Pikes Peak which is at 14,000 feet elevation
Cops have stop points when going downhill that forces you to park and cool the brakes down before going further downhill !

 

[James Vette]

When should I use 1st or 2nd?

 

[Nassau65]

If your towing anything or perhaps going down a mountain.

 

[GCorvette]

Problem with always just putting it in drive is the auto tranny has its own controller, today it has over 4 meg bytes of calibration control
IF never using other gears then the TCM (controller) learns the driver's style and adjust just for that style
That means that if seldom manually shifting the TCM has not learned that and the car is a pig when it needs more output

Interesting, I never knew that, thank you.
I use the paddles on my C6 more than the auto and some of the answers in this thread, like my two previous conversations, have surprised me as I plan to use 1st and 2nd often when I settle on my C3.

 

[teamzr1]

Anyone interested in what the GM TCM calibration looks like, in this case I used a 2009 C6 with auto tranny
Attached is a text file, so all can see and read this below is all the settings for the TCM to control the tranny
Look for example what the shift points and torque allowed when like when in normal, sport, cruise, etc

 

[Nassau65]

Just thinking about what’s been said about using 1st & 2nd gears on old style and now ancient auto gearboxes as in the C3, will it be good for the box to be used in that way on a regular basis?

 

[Oneball]

Just thinking about what’s been said about using 1st & 2nd gears on old style and now ancient auto gearboxes as in the C3, will it be good for the box to be used in that way on a regular basis?

It was designed to be used like that, if it can’t cope it needs rebuilding. Auto boxes hide faults quiet well. Bands and clutches are wearing parts, they’re still much the same in modern autos, the real difference is the computer control but the oily bits are much the same. You can build a hugely strong TH350/400 that’ll cope with 1000hp.

 

[Roscobbc]

Just thinking about what’s been said about using 1st & 2nd gears on old style and now ancient auto gearboxes as in the C3, will it be good for the box to be used in that way on a regular basis?

I just don't see the logic in shifting an 'old school' auto box manually - if 100% stock and without a shift kit etc it'll change slower than leaving it to its own devices.

 

[Vetman]

My C3 has a 3 speed TH400 and I have never found a need to use 1 and 2 in over 40 years of use. I have selected 1 and 2 occasionally as an acceleration experiment only without conclusion.

 

[GCorvette]

I just don't see the logic in shifting an 'old school' auto box manually - if 100% stock and without a shift kit etc it'll change slower than leaving it to its own devices.

Obviously I'm not yet an owner, but I would assume to allow you to a) Have that manual control and b) To pull harder through the revs (within tolerance) than the auto would?

 

[Nassau65]

I just don't see the logic in shifting an 'old school' auto box manually - if 100% stock and without a shift kit etc it'll change slower than leaving it to its own devices.

That’s my way of thinking also. What’s the point?

 

[Stingray]

Here is an example of a C7 with auto tranny as the engine and tranny being controlled as how much torque is allowed, and when

Here is just one of the several torque tables in the tune, as you see depending on the RPM how much torque the TCM will allow as output
As you see if using D only and that also means lower RPMS then less torque will be allowed so good reason to downshift,
raise the load, torques up the drivetrain and allow as much as 100 ft/lbs more torque

Consider if driving up hill and having to push the mass yet TCM only allowing 2/3rds of the torque, add setting the Corvette into touring mode
and it's a slug in D only
Reason Corvette has had auto tranny paddle shifters as even GM knows using D only sucks and is boring

Having lived with an A8 and driven it in all modes I'd say that's a highly dubious generalisation. If you've been driving around gently in Tour mode in D and jump on the throttle the transmission immediately knows the car is being asked to do more work and reacts accordingly. It'll stick itself in a higher performance mode until it decides the driver has settled down again. And the paddles don't seem do anything that can't be achieved with the throttle pedal in terms of driving mode.

Sport mode locks the car out of Touring mode, but
Touring mode doesn't mean the transmission can't access its Sport program if that's the way you're driving.

I'd cheerfully bet an A8 is quicker when it's changing gears itself than if the driver starts clicking paddles. The only practical use of the paddles in my opinion is for an occasional downchange ready for an overtake.

 

[teamzr1]

The TCM uses adaptive strategy learning
Drive around for a few weeks just cruising around, see how the tranny shifts
Then disconnect the battery for like 1 minute which flushing out all that TCM learned
Go for a drive and see how the tranny reacts differently

The tune in the TCM as I mentioned as mentioned has over 4,000,000 bytes how tranny will be commanded under
all types of driving conditions and even the commanded shift times for up and downshifts are programmed differently
for those conditions and user modes

Use a OBD-II scanner in record mode and then replay and analyze all the TCM data when just cruising around and then
when using different modes, manual shifting and higher engine RPMs and loads, and you'll see it becomes clear why
GM set different tranny modes the driver can turn on and off and why using the paddle shifters have shorter shift times and what
MPH up and down shifts are done

You see the Adaptive Learn has it own tuning tables