Transmission kicks into passing gear on its own

1992 BUICK ROADMASTER
289,998 MILES • 5.7L • V8 • 2WD • AUTOMATIC
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EDDIE JIMENEZ SR.
  • MEMBER
  • 4 POSTS
My transmission gets all gears but I have noticed that when on the freeway it has been kicking itself into passing gear. can you please let me know what is wrong with it?
Mar 14, 2018 at 12:05 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good morning.

There is a throttle cable that controls shifting points up nd down. It is possible it is out of adjustment.

It is on the intake manifold behind the carburetor driver side. the cable moves back and forth and changes throttle pressure which regulates shifting. by moving the cable back and forth it will change shift point and quality.

Roy
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Mar 14, 2018 at 12:23 AM
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EDDIE JIMENEZ SR.
  • MEMBER
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Good morning .

Okay, now why would that cable suddenly get out of adjustment?
Mar 14, 2018 at 12:26 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Could be wear from age, valve body, cable coming loose down at the transmission, cable itself.

Do a visual inspection first to be sure nothing is loose or broken.

How long since the oil/filter has been changed in the transmission?

Roy
Mar 14, 2018 at 12:35 AM
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EDDIE JIMENEZ SR.
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  • 4 POSTS
About a month ago.
Mar 14, 2018 at 12:37 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Okay, I would check all the externals and try moving the cable and see if it helps.

Roy
Mar 14, 2018 at 12:46 AM
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