Whos got 4-2/3-2 downshift delay bangs?
Jun 20, 2003 | 05:45 PM
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Whos got 4-2/3-2 downshift delay bangs?
Well I tried posting this earlier but hey...as you may know the 4L60E is a pretty stupid transmission in stock form. Delay bangs, soft and slow shifts, etc. I did more research and came up with a way to get rid of this kickdown delay.
First off, when you go to kickdown from 4th to 2nd or 3rd to 2nd I get a slight delay between the kickdown of the gear to the next set. Granted it is quick it isn't the best thing for the trans internally. This is due to the 2-4 band releasing too fast for the clutch pack to engage.
What you do is take a check ball out of the valve body. The No. 6 check ball is to be removed thereby adding additional fluid flow to the overrun clutch pack (there are two overruns). This greatly speeds up the kickdown process. In all of GM's intelligence they did this for soft upshifts to please Grandma, Soccer Moms, and the like...but caused the kickdown problem in the process. Funny how taking something out of the trans will make it better.
Also another problem here is the servo pin. There are three different pins from the 700R4 to the 4L60E. The best pin is an old 700R4 Wide Band three ringed tipped one, but as those came in the 700's finding one is sorta tough. You will most likey use what you have. Typically you want the 2-4 band clearance around 1/16" to 1/8"...the closer to 1/16" the better. Rememeber most factory stuff is massed produced and vary from vehicle to vehicle greatly.
The Superior Billet intermediate servo come with an add on pin tip of .150" (around 5/32") that you can hammer on the servo pin and grind to the proper length. To check the band clearance you need a prybar to push on the servo cover to see how far in it will move (with trans in vehicle) or just push on it by hand (trans outside of vehicle). If the band it too tight it will bind/drag and if too loose will cause slop/delays.
Now that should help one very bad flaw in the 4L60E, enjoy your proper kickdown!
Links for servo install...
http://www.jetchip.com/Instructions/4thgearServos.PDF
http://www.jetchip.com/Instructions/7004L60Eservos.PDF
First off, when you go to kickdown from 4th to 2nd or 3rd to 2nd I get a slight delay between the kickdown of the gear to the next set. Granted it is quick it isn't the best thing for the trans internally. This is due to the 2-4 band releasing too fast for the clutch pack to engage.
What you do is take a check ball out of the valve body. The No. 6 check ball is to be removed thereby adding additional fluid flow to the overrun clutch pack (there are two overruns). This greatly speeds up the kickdown process. In all of GM's intelligence they did this for soft upshifts to please Grandma, Soccer Moms, and the like...but caused the kickdown problem in the process. Funny how taking something out of the trans will make it better.
Also another problem here is the servo pin. There are three different pins from the 700R4 to the 4L60E. The best pin is an old 700R4 Wide Band three ringed tipped one, but as those came in the 700's finding one is sorta tough. You will most likey use what you have. Typically you want the 2-4 band clearance around 1/16" to 1/8"...the closer to 1/16" the better. Rememeber most factory stuff is massed produced and vary from vehicle to vehicle greatly.
The Superior Billet intermediate servo come with an add on pin tip of .150" (around 5/32") that you can hammer on the servo pin and grind to the proper length. To check the band clearance you need a prybar to push on the servo cover to see how far in it will move (with trans in vehicle) or just push on it by hand (trans outside of vehicle). If the band it too tight it will bind/drag and if too loose will cause slop/delays.
Now that should help one very bad flaw in the 4L60E, enjoy your proper kickdown!
Links for servo install...
http://www.jetchip.com/Instructions/4thgearServos.PDF
http://www.jetchip.com/Instructions/7004L60Eservos.PDF
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