Transmission lost all forward gears, code P1680

1996 CHEVROLET BLAZER
123,000 MILES • 4.3L • 6 CYL • 4WD • AUTOMATIC
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BOBBLUESEA
  • MEMBER
  • 1 POST
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.
Sep 16, 2020 at 7:26 PM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 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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Sep 16, 2020 at 9:16 PM
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