3-4 shift problem
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TECH Enthusiast
Joined: Feb 2012
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From: Orlando
3-4 shift problem I drive in D here in hot Miami until I get to about 45mph and up and then I'll pop it into OD but lately sometimes when I shift from D to OD itll act like its in neutral for a split second and then shift. Is this slippage or a failing solenoid? What are your thoughts? This doesn't happen every time. Only a couple times it's happened. Today I drove 53 miles and didn't happen once. But happened twice yesterday in my 45 mile drive.
Thread Starter
TECH Enthusiast
Joined: Feb 2012
Posts: 631
Likes: 0
From: Orlando
I drive in D here in hot Miami until I get to about 45mph and up and then I'll pop it into OD but lately sometimes when I shift from D to OD itll act like its in neutral for a split second and then shift. Is this slippage or a failing solenoid? What are your thoughts? This doesn't happen every time. Only a couple times it's happened. Today I drove 53 miles and didn't happen once. But happened twice yesterday in my 45 mile drive.
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
It could be the band slipping. I usually read that 2nd slips before 4th, but not always.
Its easy to check the band:
With a small ruler next to the servo cover, press on the servo cover with a crowbar and estimate how much it moves in. This is called the end play. Spec is 1/16 to 1/8". Around 3/16" you will start to experience slippage.
Since 4th gear is a combination of 2nd and 3rd gear, if gears 1 thru 3 work, it is unlikely to be a solenoid, PCM, wiring or internal problem (other than the band).
Much less common than a worn band, we have had these causes reported for 4th gear problems:
* Cracked 4th gear piston in the servo
* Valve body problem - perhaps the 3-4 Relay or 4-3 sequence valve
Check the servo end play. If it is excessive, I have documented how to lengthen the servo pin and thereby get another 5000 to 10,000 miles out of the trans before it needs a rebuild:
Lengthened Servo Pin:
https://ls1tech.com/forums/automatic...t-trouble.html
https://ls1tech.com/forums/automatic...-gear-all.html
https://ls1tech.com/forums/automatic...ckup-help.html
Worked:
https://ls1tech.com/forums/automatic...cond-only.html
https://ls1tech.com/forums/automatic...e-2-fixed.html
https://ls1tech.com/forums/automatic...-4th-gear.html
Its easy to check the band:
With a small ruler next to the servo cover, press on the servo cover with a crowbar and estimate how much it moves in. This is called the end play. Spec is 1/16 to 1/8". Around 3/16" you will start to experience slippage.
Since 4th gear is a combination of 2nd and 3rd gear, if gears 1 thru 3 work, it is unlikely to be a solenoid, PCM, wiring or internal problem (other than the band).
Much less common than a worn band, we have had these causes reported for 4th gear problems:
* Cracked 4th gear piston in the servo
* Valve body problem - perhaps the 3-4 Relay or 4-3 sequence valve
Check the servo end play. If it is excessive, I have documented how to lengthen the servo pin and thereby get another 5000 to 10,000 miles out of the trans before it needs a rebuild:
Lengthened Servo Pin:
https://ls1tech.com/forums/automatic...t-trouble.html
https://ls1tech.com/forums/automatic...-gear-all.html
https://ls1tech.com/forums/automatic...ckup-help.html
Worked:
https://ls1tech.com/forums/automatic...cond-only.html
https://ls1tech.com/forums/automatic...e-2-fixed.html
https://ls1tech.com/forums/automatic...-4th-gear.html
Registered User
Joined: May 2016
Posts: 3
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sounds likes your having problems with your 3/4 housing very common in the 4l60e always recommend people to run trans cooler to boost up the life of a trans but
mrvedit is right Since 4th gear is a combination of 2nd and 3rd gear, if gears 1 thru 3 work, it is unlikely to be a solenoid, PCM, wiring or internal problem (other than the band).
mrvedit is right Since 4th gear is a combination of 2nd and 3rd gear, if gears 1 thru 3 work, it is unlikely to be a solenoid, PCM, wiring or internal problem (other than the band).
