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Old 05-04-2018, 03:13 PM
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Rogillio
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I am new to manual transmissions. Driven a motorcycle all my life so understand shifting but this is a different beast. Been 4 + months now and I’m getting the hang of it. I no longer have the humiliating experience of killing the engine taking off from a red light. Most of the time I have no problem shifting but occasional I have a hard time finding second. I will usually just give up after a bit and go to third. Seems to happen when I am driving aggressively. So couple of questions.

Is there some some sort of limiter to keep you from going into 2nd if the rpms are too high?

is it ok to go from 1 to 3?

And a really lazy stupid question....if I’m in fourth and coming up to red light, can I just bump the shifter to to neutral w/o pressing the clutch? Haven’t tried it yet as I don’t want to grind gears. Just don’t know enough about the mechanics of a tranny to know how the gears are disengaging.
Old 05-04-2018, 05:49 PM
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Shaka
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Originally Posted by Rogillio
I am new to manual transmissions. Driven a motorcycle all my life so understand shifting but this is a different beast. Been 4 + months now and I’m getting the hang of it. I no longer have the humiliating experience of killing the engine taking off from a red light. Most of the time I have no problem shifting but occasional I have a hard time finding second. I will usually just give up after a bit and go to third. Seems to happen when I am driving aggressively. So couple of questions.

Is there some some sort of limiter to keep you from going into 2nd if the rpms are too high?

is it ok to go from 1 to 3?

And a really lazy stupid question....if I’m in fourth and coming up to red light, can I just bump the shifter to to neutral w/o pressing the clutch? Haven’t tried it yet as I don’t want to grind gears. Just don’t know enough about the mechanics of a tranny to know how the gears are disengaging.



Old 05-04-2018, 08:43 PM
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Trackaholic
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Corvette has a "feature" that locks out 2nd under certain conditions to improve fuel economy. It's knwn as "skip shift" and is intended to divert you to 4th gear. There are aftermarket cable harnesses that can defeat it if you find it annoying. The owners manual will spell out the details of the conditions under which it will activate.

Regarding question #2, you can shift out of a gear to neutral without the clutch as long as the gears are very lightly loaded. The more load on the gears, the more difficult it will be to do, and at some point it will start causing damage. Might be fun to play around with, but safer just to use the clutch. FYI, if you are really good, and can match revs extremely well, you can shift into gear without the clutch as well. Just has the potential to cause even more damage.

-T

Last edited by Trackaholic; 05-04-2018 at 08:43 PM.
Old 05-04-2018, 10:36 PM
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sTz
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As mentioned, there is a 2nd gear skip-shift for fuel economy purposes, but I’ve only experienced it a few times as I tend to rev higher when shifting.

Yes, it’s OK to go from 1-3...

Yes, you can bump into neutral, but it’s not recommended.
Old 05-04-2018, 10:40 PM
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iclick
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Originally Posted by Rogillio
[left]Most of the time I have no problem shifting but occasional I have a hard time finding second. I will usually just give up after a bit and go to third.
Not sure what's going on there, but might be caused by CAGS (Computer Assisted Gear Shift), or as I call it CIGS (Computer Interference with Gear Shifting). There's a brief blurb about it in the owner's manual ("1-4 Shift Message", p. 195 in my 2017 manual). Basically it shows a message on the DIC and forces you to shift from 1-4 when certain conditions occur, always under unagressive driving conditions. If you find it intrusive (like I do) you can buy a CAGS eliminator (Ebay and forum vendors) for as little as $11 that will nix that "feature."

Is it ok to go from 1 to 3?
Yes, if you don't lug the engine in 3rd. I used to do that routinely in my C6 but the C7 gearing is a bit different and I rarely do it anymore.

...can I just bump the shifter to to neutral w/o pressing the clutch?
You can do it if the RPMs match the gear speeds, but I've always understood that this may cause undo wear on synchronizers, so I don't do it.
Old 05-04-2018, 11:05 PM
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saleen556
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If your having a problem with second driving aggressively then it's not CAGS. It will only block you at easy throttle between 15-20mph. If your doing this before the transmission warms up that could be the issue. As far as going in to neutral at a stop just hit the clutch and pop out of gear to coast/brake. Not a great idea long term not using the clutch. You chose the FUN transmission so enjoy.
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Old 05-05-2018, 12:10 AM
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jtranger
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Don't forget to use your rev match..it is superb
Old 05-05-2018, 12:12 AM
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Skid Row Joe
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First of all, you've got to push the clutch way far in when shifting. Second of all, you need to make a crisp shift. No dilly dallying. You've got to be decisive in your movement. If you never kill it when starting out, you're way ahead of most manual newbys. My C7 M7 is by far the easiest manual transmission I've ever owned and driven. It rivals my '65 Chevy Wagon I6, with 3-on-the-tree, in ease of operation!
Old 05-05-2018, 07:15 AM
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cowboy casey
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It took me about 5000 miles to get the GM clutch down and then the heaven's opened up and everything was great in the world.. The best advice I received on the first to second shift was make sure the tranny is warm and shift it like you mean it, meaning grab that stick shift and put it in second with some force

(and I put Redline D4 oil in, best thing for a Tremac you can do, but many will not do it because of warranty)

Old 05-05-2018, 07:55 AM
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JerryU
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Originally Posted by Rogillio
I am new to manual transmissions. Driven a motorcycle all my life so understand shifting but this is a different beast. Been 4 + months now and I’m getting the hang of it. I no longer have the humiliating experience of killing the engine taking off from a red light. Most of the time I have no problem shifting but occasional I have a hard time finding second. I will usually just give up after a bit and go to third. Seems to happen when I am driving aggressively. So couple of questions.

Is there some some sort of limiter to keep you from going into 2nd if the rpms are too high?

is it ok to go from 1 to 3?

And a really lazy stupid question....if I’m in fourth and coming up to red light, can I just bump the shifter to to neutral w/o pressing the clutch? Haven’t tried it yet as I don’t want to grind gears. Just don’t know enough about the mechanics of a tranny to know how the gears are disengaging.
Sounds like you may occationally getting caught in the foolish GM "feature" that helps them get a few more tenths mpg in the required EPA mpg test!

It forces a 1st to 4th shift if shifting at around ~1600 rpm in the narrow range needed for the EPA test!

A way many of us avoid this is by installing a ~$15 device that plugs in the wire harness and puts a resistor in the like making the computer think it activates the blocking solenoid pin! If you are handy when you have the car jacked up or on a lift, a <5 minute install!

This is a PDF of the install: http://netwelding.com/Skip_shift_Eliminator.pdf

DETAILS
This unwanted "feature" has been in Vettes for some years. If you read the Owner's Manual, to get "best" mpg it suggests shifting at low rpm's. Some at low as 1000 rpm. The first shift from first is at a low rpm that will force a 1st to 4th! Then the 4th to 5th etc are at very low rpm most would consider lugging the engine-but technically OK with the minimum throttle they no doubt employ for the EPA test! Can't believe anyone drives a Vette (or any car) that way!

As some, you can watch your speeds or as many of us do, install what is referred to as a CAGS Eliminator for a few dollars. Did that in my C6, C7 2014 and now my Grand Sport! Watched one of the gals in "All Girls Garage" TV Show do it with a Camaro that was on a lift in about a minute, real time! It just plugs into the wire harness. In some instances, such as in bumper to bumper traffic, the forced shift is a PIA! With the eliminator device installed you can shift where you want when you want!

TRANS:
The M7 is a conventional transmission not a sequential motorcycle trans. The syncro's "won't like" shifting into neutral without the clutch depressed. Sounds like you might be interested on how the trans works and more important just what the syncro's must do in milliseconds changing the speed of the very large gear clusters. This is a great video that I find is excellent even being a "gearhead" since my early teens!

REV MATCH:
The C7 Tremic M7 has a new feature called rev match! I find it very useful around town and for lower rpm shifting where my usual heal-toe rev match was not as accurate as what I have done for 60 years driving only standard shifts as my daily driver! With 7 speeds and an engine that has a wide torque range, unlike motorcycle engines, no need to shift sequentially. For example, when driving in town at 45/50 mph in 5th and turning I go directly into 3rd. Rev Match makes that a perfectly smooth transition my increasing the rpm to match the required engine rpm for the lower gear. The same when on the Interstate and exiting. No need to go through two other overdrives, 6th and 5th, just shift directly to direct drive 4th. Rev match makes the shift perfectly smooth.

I am quite good at matching the rpms at a one gear change when the engine rpm in the lower gear will be closer to redline. Much harder to modulate the throttle to say 2500 to 3000 rpm at lower speeds when not driving in anger!

Have fun.

Last edited by JerryU; 05-05-2018 at 08:37 AM.
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Old 05-06-2018, 01:28 AM
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jimmbbo
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After encountering the dreaded 1st to 4th shift block "feature", I decided to avoid it by running the RPM up a bit and shifting 1-2 or shifting 1-3. The car has enough power so it's happy either way
For decades, I have routinely shifted into neutral when the engine/trans RPMs are matched and the gears are unloaded.
Old 05-06-2018, 07:56 AM
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Ok, a synchro doesn't care if you shift into neutral. They are only involved when you are shifting from one gear to another gear. If the transmission is lightly loaded, you can shift into neutral with no clutch and no problem. It has nothing to do with being sequential or not. (in fact, with a sequential transmission, you have to go through the other gears to get to neutral). It won't hurt a thing.

You can also shift from 1st to 3ed or 4th or 5th... if you want to. (I have no idea why you would want to, but you can...) As long as you don't cause the engine to stall or lug.
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Old 05-06-2018, 12:40 PM
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Originally Posted by cowboy casey
...and I put Redline D4 oil in, best thing for a Tremac you can do, but many will not do it because of warranty.
Won't violate warranty since it meets Dexron III specs.

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