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      08-21-2017, 09:54 PM   #45
mackeroni
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Quote:
Originally Posted by jlc45 View Post
Some of the comments and suggestions here are correct and some of them do not have any technical basis. I have built thousands of automatic transmissions and a few manuals and replaced dozens of clutches on a variety of cars. But my knowledge is not current since I am retired. How many of the folks offering advice here have ever even seen a transmission apart? In many instances problems are related to clutch malfunctions and the trans is not the problem. The "internals" of the trans do not stop in second gear. The gears and shafts stop rotating only when the vehicle is stopped and the clutch is disengaged. Like when you are stopped at a light with the clutch pedal in.
(Or the engine is off and the car is stopped. :-) )
The throwout bearing acts on the fingers of the pressure plate moving it "backwards" and when the clutch pedal is depressed the clutch disc is no longer able to "grab onto" the flywheel. The crank only moves forward and back to a very minor extent, a few thousandths of an inch and this has no affect on shifting performance.
There is no technical reason why shifting into second before shifting into first should make any difference. If you think this is important, please explain why. Similarly, there is no harm caused by resting ones hand lightly on the shifter while driving. Again, please explain why you believe this will damage the transmission. Lightly being a key word here. There is no technical reason why you can't skip a gear while shifting. I go from 3rd to 5th quite often and have been doing this for years. It is easier to rebuild an auto trans than a manual in my experience. As I said, I have R&R and completely rebuilt over a thousand automatics. I have seen Fords with no second gear, which shifted from 1st to third and the owners did not even realize they had a problem.
The most obvious reason synchros malfunction is because they crack and lose their ability to grab onto the cone portion of their corresponding gear. In that case the trans must be disassembled to repair the defect.
I appreciate your comments. Especially regarding skipping gears in a manual transmission. Unless I am in a big hurry, I routinely skip gears as I move from 1st to 6th. Typically, I shift 1-3-6 or 1-2-4-6 from a dead stop, or just 2-4-6 from a rolling stop. I take care to not lug the engine when shifting this way, and I am convinced that by reducing the number of shifts, I am extending the life of the clutch.

Peace... Mack
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      08-22-2017, 10:35 AM   #46
Matticus91
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Quote:
Originally Posted by jlc45 View Post
Some of the comments and suggestions here are correct and some of them do not have any technical basis. I have built thousands of automatic transmissions and a few manuals and replaced dozens of clutches on a variety of cars. But my knowledge is not current since I am retired. How many of the folks offering advice here have ever even seen a transmission apart? In many instances problems are related to clutch malfunctions and the trans is not the problem. The "internals" of the trans do not stop in second gear. The gears and shafts stop rotating only when the vehicle is stopped and the clutch is disengaged. Like when you are stopped at a light with the clutch pedal in.
(Or the engine is off and the car is stopped. :-) )
The throwout bearing acts on the fingers of the pressure plate moving it "backwards" and when the clutch pedal is depressed the clutch disc is no longer able to "grab onto" the flywheel. The crank only moves forward and back to a very minor extent, a few thousandths of an inch and this has no affect on shifting performance.
There is no technical reason why shifting into second before shifting into first should make any difference. If you think this is important, please explain why. Similarly, there is no harm caused by resting ones hand lightly on the shifter while driving. Again, please explain why you believe this will damage the transmission. Lightly being a key word here. There is no technical reason why you can't skip a gear while shifting. I go from 3rd to 5th quite often and have been doing this for years. It is easier to rebuild an auto trans than a manual in my experience. As I said, I have R&R and completely rebuilt over a thousand automatics. I have seen Fords with no second gear, which shifted from 1st to third and the owners did not even realize they had a problem.
The most obvious reason synchros malfunction is because they crack and lose their ability to grab onto the cone portion of their corresponding gear. In that case the trans must be disassembled to repair the defect.
Thanks for your input! Shifting from 2nd to 1st is something I do when coming to a stop since it puts less wear on the "cones" of the synchros. The technical difference being the speed at which the transmission components are rotating in relation to the flywheel. Less difference in relative speed means the synchros will not need to "work" as hard to get everything to mesh together.

As for the resting of your hand on the shifter, that's about the shift lever itself and not the internals of the transmission. Weight on the lever just *slightly* accelerates wear on the bushings and can lead to some unwanted play in the lever.
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      08-22-2017, 12:28 PM   #47
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Quote:
Originally Posted by Matticus91 View Post
As for the resting of your hand on the shifter, that's about the shift lever itself and not the internals of the transmission. Weight on the lever just *slightly* accelerates wear on the bushings and can lead to some unwanted play in the lever.
Bad habit I used to have back in my manual days.
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      08-22-2017, 01:59 PM   #48
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Quote:
Originally Posted by Esteban View Post
Bad habit I used to have back in my manual days.
One thing I never did when I owened the MS3 before I got into the 135i. Leaving hand on shifter and leaving foot on clutch pedal. My momo slapped me when I first learned how to drive stick (she taught me even though my Dad drove 18 wheelers for the longest time).
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      08-22-2017, 02:29 PM   #49
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Originally Posted by Havocsteve View Post
One thing I never did when I owened the MS3 before I got into the 135i. Leaving hand on shifter and leaving foot on clutch pedal. My momo slapped me when I first learned how to drive stick (she taught me even though my Dad drove 18 wheelers for the longest time).
You're a lucky guy. My momo was dead when I learned how to drive and my dad was too drunk to teach me. Learned all my bad habits on my own. I know, I know... cry me a river. lol
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      08-22-2017, 02:43 PM   #50
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The old adage when learning how to drive stick....

Grind them till you find them..... LOL.
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      08-22-2017, 02:48 PM   #51
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Originally Posted by zx10guy View Post
The old adage when learning how to drive stick....

Grind them till you find them..... LOL.
Cringed when I read that LOL
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      08-23-2017, 11:28 AM   #52
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You should shift into first when the vehicle is stopped and the clutch pedal is in.
There is no need to shift into second and then into first.
If you shift into second it has no effect on what the first gear is doing.
If the clutch is disengaged the input shaft and the countershaft can stop turning when the driveshaft stops turning when the car comes to a stop. Everything in the trans stops turning when the car is stopped and the clutch pedal is in. (the clutch pressure plate and the throwout bearing are turning but they play no role in shifting gears.) The act of shifting into first gear means you are "locking" the gear itself to the output shaft. Older cars did not even have synchros for first gear. The first gear synchros enable the trans to be shifted into first gear without grinding when the car is rolling forward or backward at slow speeds.
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