Sometime shifts hard , Turn off at red light shifts fine?

Sometime shifts hard , Turn off at red light shifts fine?

Postby AstroVanDan [OP] » August 14th 2018, 2:50pm

Two years ago I had my transmission rebuilt , when I got it back it shifted very hard . Took it back and reprogrammed the computer and it was fine . Now and then now it will shift hard at 55, 65, 70, 75. I can stop at a red light turn it off and restart and its fine. This happens a few times a week. What do you think? Thanks
Last edited by AstroVanDan on August 14th 2018, 4:00pm, edited 1 time in total.
Original Poster [OP]
AstroVanDan
Fueling (1/4 tank)
Fueling (1/4 tank)
Years of Membership: AstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full years
Posts: 25
Topics: 9
Images: 4
Joined: June 2015
Location: Longwood , Florida
Gender: Male
Alias (AKA): AstroVanDan
Van Model Year: 2001
Van Make/Model: Chevrolet Astro

Re: Sometime shifts hard , Turn off at red light shifts fine

Postby plymouthcranbrook » August 14th 2018, 3:07pm

Probably a computer issue. Our school buses do that often and need a "reboot" done by turning of the engine and waiting a couple of minutes to restart. usually fixes it till the next time.
Last edited by plymouthcranbrook on August 15th 2018, 3:57am, edited 1 time in total.
plymouthcranbrook
Firing on 1 Cylinder (L1)
Firing on 1 Cylinder (L1)
Years of Membership: plymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full yearsplymouthcranbrook has been a member for 11 full years
Posts: 184
Topics: 16
Joined: November 2009
Gender: Male
Alias (AKA):
Van Make/Model: Chevrolet Astro
Extra Info: allwheel drive

Re: Sometime shifts hard , Turn off at red light shifts fine

Postby AstroVanDan [OP] » August 14th 2018, 3:09pm

That's what mine is doing .
Original Poster [OP]
AstroVanDan
Fueling (1/4 tank)
Fueling (1/4 tank)
Years of Membership: AstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full yearsAstroVanDan has been a member for 5 full years
Posts: 25
Topics: 9
Images: 4
Joined: June 2015
Location: Longwood , Florida
Gender: Male
Alias (AKA): AstroVanDan
Van Model Year: 2001
Van Make/Model: Chevrolet Astro

Re: Sometime shifts hard , Turn off at red light shifts fine

Postby MattB » November 12th 2018, 1:43am

Around 1998 GM modified the 4L60e with a Soft Apply Torque Converter Function. After a bunch of miles the Valve wears and causes Slippage. The Computer calculates Slippage and Jacks up line pressure to correct this. This results in the Slam Shift 1-2. There is an easy/cheap fix for this. This kit coil-binds the PWM valve, eliminating the Soft Apply function. This fixed my Slam shift problem. The problem did major damage to the clutch pack. Full rebuild soon followed.
I haven't post the pics yet. Full 4l60e rebuild.
"Which is worse, The Evil you know or The Unknown?"
User avatar
MattB
Fueling (5/8 tank)
Fueling (5/8 tank)
Years of Membership: MattB has been a member for 3 full yearsMattB has been a member for 3 full yearsMattB has been a member for 3 full years
Posts: 70
Topics: 8
Images: 20
Joined: September 2017
Location: Northern Illinois, AKA "The Rust Belt"
Gender: Male
Alias (AKA): MattB
Van Model Year: 1999
Van Make/Model: GMC Safari
Extra Info: Rwd SLE


 
  • Related topics
    Replies
    Views
    Last post

Return to Automatic

It is currently February 27th 2021, 1:56pm

Automatic Forum
AutomaticThe purpose of an Automatic Transmission is similar to that of a manual transmission, the auto tranny's primary duty is to allow the engine to operate in its narrow range of speeds while providing a wide range of output speeds.
To create a new topic in Automatic, click this button:
Previous topic Next topic
Recent Image Attachments
Attached by:
AngryPunk
in Automatic
Views: 232
Comments: 15
Date: Feb 18 '21
Time: 11:47pm
» Read last comment
Attached by:
Youngblood
in Automatic
Views: 137
Comments: 3
Date: Jan 15 '21
Time: 1:24am
» Read last comment
Attached by:
allenstoltzfus
in Automatic
Views: 307
Comments: 11
Date: Jan 14 '21
Time: 7:36pm
» Read last comment
Attached by:
runawayjim
in Automatic
Views: 206
Comments: 5
Date: Jan 07 '21
Time: 2:09pm
» Read last comment
Attached by:
Attached by: SportsBoy
SportsBoy
in Automatic
Views: 2880
Comments: 16
Date: Jan 05 '21
Time: 11:16pm
» Read last comment
Sponsors

Who is online

Users browsing this forum: Google Adsense [Bot] and 12 guests