Question about 1991 GMC C1500

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MY 89 Chevy 5600 GVW 2WD has a 700 R 4 and it does the 3 and 4 back and forth thing. It acts like it is unlocking when you let off the gas. It has been worked on twice and I would like to have this corrected or replaced. It downshifts on flat ground with no load. Last week it went into first about 50 and the 5.7 sounded like it was about to come through the floorboard.

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Posted on Jan 02, 2017



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SOURCE: gas gauge dont work jumps back and forth is

if it jumps really fast you probably have a bad gauge/instrument cluster. if it moves back and forth with a slower/normal rate of movement you probably have a bad fuel level sending unit located in the tank.

Posted on Mar 23, 2010


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