Re: Torqueflite 727 non-repair question
[Re: fal3]
#2075975
05/18/16 05:14 PM
05/18/16 05:14 PM
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Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
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Am I hurting the transmission shifting it manually? I seem to recall that back in the day it was ill-advised to shift it manually repeatedly-forgot why though. In Drive, the rear band is not applied but in manual low the rear band is applied; on the 1-2 upshift the band has to release and the release is spring-only (Lotsa drag/overlap) this makes the band wear quicker since it was never intended to be applied/released on each shift cycle. The sprag is in little danger in normal driving in Drive but when launching hard it's preferable to manually shift.
The INTERNET, the MISinformation superhighway
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Re: Torqueflite 727 non-repair question
[Re: fal3]
#2076001
05/18/16 06:19 PM
05/18/16 06:19 PM
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Joined: Jan 2003
Posts: 75,004
U.S.S.A.
JohnRR
I Win
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I Win
Joined: Jan 2003
Posts: 75,004
U.S.S.A.
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Downshifting into 1st(low) is not recommended while moving as that puts a shock load on the sprag, it can grab faster than the band will apply.
running up my post count some more .
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Re: Torqueflite 727 non-repair question
[Re: John_Kunkel]
#2076162
05/18/16 10:49 PM
05/18/16 10:49 PM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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Am I hurting the transmission shifting it manually? I seem to recall that back in the day it was ill-advised to shift it manually repeatedly-forgot why though. In Drive, the rear band is not applied but in manual low the rear band is applied; on the 1-2 upshift the band has to release and the release is spring-only (Lotsa drag/overlap) this makes the band wear quicker since it was never intended to be applied/released on each shift cycle. The sprag is in little danger in normal driving in Drive but when launching hard it's preferable to manually shift. John are you sayin that manually shifting a "regular" TF is hard on the rear band no matter what (easy shifting/hard launch) & if launching hard it is still bad for it but when launching hard you DO want to manually shift as that is easier on the sprag? I had always read from decades ago that manually upshifting a regular TF was not recommended.
live every 24 hour block of time like it's your last day on earth
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Re: Torqueflite 727 non-repair question
[Re: RapidRobert]
#2076500
05/19/16 02:23 PM
05/19/16 02:23 PM
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Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
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On a stock TF, the rear band applies in two stages, the spring-cushioned inner piston must compress before the larger main piston makes the final application. When released on the 1-2 upshift it also releases in two stages, this causes a delay in the release which equates to a lot of drag (wear) on the band and there is significant overlap because both the rear and kickdown bands are applied at the same time.
This is also true when launching hard in manual low but the safety of applying the band to protect the sprag outweighs the wear on the band.
Modified rear servos with billet pistons and heavier release springs mitigate the wear/overlap somewhat but it's still not advisable to manually shift on a regular basis.
The INTERNET, the MISinformation superhighway
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Re: Torqueflite 727 non-repair question
[Re: John_Kunkel]
#2076679
05/19/16 07:23 PM
05/19/16 07:23 PM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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John you are the man (as always!).
live every 24 hour block of time like it's your last day on earth
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Re: Torqueflite 727 non-repair question
[Re: John_Kunkel]
#2076867
05/20/16 12:52 AM
05/20/16 12:52 AM
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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On a stock TF, the rear band applies in two stages, the spring-cushioned inner piston must compress before the larger main piston makes the final application. When released on the 1-2 upshift it also releases in two stages, this causes a delay in the release which equates to a lot of drag (wear) on the band and there is significant overlap because both the rear and kickdown bands are applied at the same time.
This is also true when launching hard in manual low but the safety of applying the band to protect the sprag outweighs the wear on the band.
Modified rear servos with billet pistons and heavier release springs mitigate the wear/overlap somewhat but it's still not advisable to manually shift on a regular basis.
that confirms (to me) that me & John ain't even in the same city as far as knowledge goes. I can meticulously rebuild one & do a shift kit but that's about it
live every 24 hour block of time like it's your last day on earth
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Re: Torqueflite 727 non-repair question
[Re: SportF]
#2078343
05/22/16 04:55 PM
05/22/16 04:55 PM
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Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
John_Kunkel
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 25,785
Rio Linda, CA
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Yes, don't shift your trans manually. Save it for the next guy. You might wear out the band and have fun at the same time If you want to have fun shifting all the time, get a 4-speed.
The INTERNET, the MISinformation superhighway
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Re: Torqueflite 727 non-repair question
[Re: John_Kunkel]
#2078462
05/22/16 09:45 PM
05/22/16 09:45 PM
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Joined: Jan 2008
Posts: 1,212
Minn
SportF
pro stock
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pro stock
Joined: Jan 2008
Posts: 1,212
Minn
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Yes, don't shift your trans manually. Save it for the next guy. You might wear out the band and have fun at the same time If you want to have fun shifting all the time, get a 4-speed. Life is short, play hard.
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