Transmission lost all forward gears, code P1680

BOBBLUESEA

MEMBER
1996 CHEVROLET BLAZER
4.3L
6 CYL
4WD
AUTOMATIC
123,000 MILES

Departed freeway. Pulled away from exit ramp and lost all forward gears in about 10-20 yards. No forward gears but strong reverse gear. Check engine light had been on since I bought it and have driven it a few thousand miles and the only code is P1680.

1 Reply

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

The forward is controlled by the forward clutch pack inside the transmission. Chances are that these clutches have failed and will not allow forward movement.

https://www.2carpros.com/articles/automatic-transmission-problems

I would drop the pan and see if there is any metal in the pan or on the magnet.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

This sounds like either a rebuilt or used transmission will be needed.

https://www.2carpros.com/articles/transmission-replacement-removal-manual

As far as the code, can you verify the code number? 1680 does not show in my code list.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Roy

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