Transfer case not working properly

1999 GMC JIMMY
220,000 MILES • 4.3L • 6 CYL • 4WD • AUTOMATIC
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HRNDZ69
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I have checked and replaced all vacuum lines and inspected the vacuum actuator and cable going to front differential and everything seems to be working fine. transfer control module and motor seems to be working properly, with all that being said, I tried to manually shift the transfer case into 2 wheel drive but seems to only shift in 2 gears and not 4, my? Is, should it have 4 different gears, by the way I have the 4 button selector switch.
Feb 9, 2020 at 6:45 AM
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PORTAFISHING
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My name is Stephen,

If I'm understanding correctly your shifting into 2 wheel drive and your transmission is not shifting in all 4 gears?
Feb 9, 2020 at 5:50 PM
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HRNDZ69
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Hi Stephen,

it's in 4 lo, it acts like it's shifting into different gears, but just goes back to 4 lo.
Feb 10, 2020 at 7:03 AM
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PORTAFISHING
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Sounds like an actuator problem like it's trying to come out but it's not fully disengaging. So it goes right back into 4 Low. Do you have access to a scan tool?
Feb 10, 2020 at 7:26 AM
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HRNDZ69
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No I don't.
Feb 10, 2020 at 8:36 AM
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HRNDZ69
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Where would I find the actuator that you are talking about, I know where the actuator is under the battery, and the one on the firewall, but is there another somewhere else?
Feb 11, 2020 at 7:28 AM
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PORTAFISHING
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Here are some testing procedures to help figure out what's going on. this will also help you locate the encoder.
Stephen
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Feb 11, 2020 at 9:20 AM