4L60 1st Gear Shifting Issues
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From: Muscle Shoals AL,
4L60 1st Gear Shifting Issues Ok so here's my problem. Car shifts and drives perfect under normal driving conditions. However If I hammer it from a dead stop, when it goes to the first shift which should be 1~2 gear shift it bounces off of the rev limiter badly. Thought and suggestions as to what may be going on with it. The 1~2gear change is set about 6050 RPM and my rev limiter is set about 7100.
Motor makes close to 500 RWHP before N20. I also am running a Yank 3600 convertor. Any ideas or suggestions as to what the issue may be would be greatly appreciated.
Thanks,
Eric
Motor makes close to 500 RWHP before N20. I also am running a Yank 3600 convertor. Any ideas or suggestions as to what the issue may be would be greatly appreciated.
Thanks,
Eric
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Joined: Aug 2010
Posts: 7,323
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From: Ann Arbor, MI
Check the end play of the servo; excessive end play indicates the band is worn.
Using a crow bar and a ruler press down on the servo cover and estimate how much it moves.
Between about 1/16" and 1/8" is within spec. By 3/16" the band often starts to slip in either 2nd or 4th gear.
Using a crow bar and a ruler press down on the servo cover and estimate how much it moves.
Between about 1/16" and 1/8" is within spec. By 3/16" the band often starts to slip in either 2nd or 4th gear.
Thread Starter
TECH Regular
iTrader: (7)
Joined: Aug 2009
Posts: 444
Likes: 2
From: Muscle Shoals AL,
Check the end play of the servo; excessive end play indicates the band is worn.
Using a crow bar and a ruler press down on the servo cover and estimate how much it moves.
Between about 1/16" and 1/8" is within spec. By 3/16" the band often starts to slip in either 2nd or 4th gear.
Using a crow bar and a ruler press down on the servo cover and estimate how much it moves.
Between about 1/16" and 1/8" is within spec. By 3/16" the band often starts to slip in either 2nd or 4th gear.
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Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
The basic tools for transmission diagnosis are a scanner that can command gears and trans pressure gauge.
Are you saying it is stuck in 1st?
Does the car start in 2nd gear if you shift to [D2]?
I would want to rule out the shift solenoids and the PCM before pulling the trans, assuming the servo end play was OK.
Are you saying it is stuck in 1st?
Does the car start in 2nd gear if you shift to [D2]?
I would want to rule out the shift solenoids and the PCM before pulling the trans, assuming the servo end play was OK.
