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Discussion Starter #1
I have a 2005 LLY, 4WD, Crew Cab with a 5 speed allison. The gear selector at the column was acting up, not going into park for several seconds, and would not go into 1st or 2nd at all. I changed the NSBU switch thinking it would fix my problems. It fixed the slow park engagement, but it still cannot select 1st or 2nd gear. It is as if the selector at the column is bottomed out at 3rd gear. You can feel the cable getting tight when trying to go to second, but I don't want to force it. I heard that the electrical grounds can go bad and not allow the valves to open/close or something like that? Could this be my issue? Any and all help is greatly appreciated. New to the site but this site has already helped me out a bunch with a few other problems, so thank you!.
 

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Discussion Starter #2
I just realized I posted this in the wrong forum, my bad.
 

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Probably the shift linkage is loose or worn. Disconnect the cable from the trans shift lever at the trans-- now shift the trans through the gears and watch the display. If it works OK, and the lever is tight-- replace the cable.

Be sure to block the wheels and apply the emergency brake. :)
 

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Discussion Starter #4
I have tried going through the gears with the engine off, and it goes through all the gears fine. I also tried putting it in third (the last gear before it hangs up), turning the truck off in gear, and then turning the shaft with a cresent and it won't budge into 2 or 1 but will go back into N D R and P. :mad: The cable is slightly damaged, but it moves freely with the linkage unhooked. The bracket holding the lower boot by the NSBU switch was broken, so I fastened it tightly with some wire.
 

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Discussion Starter #5
Is there any adjustment on the NSBU switch? When I installed the switch I was sure to keep it in neutral, but I bought a GM switch without the neutral metal clip on the switch, so is there any way that the switch is incorrectly installed? The problem began when I installed the last NSBU, the one before this most recent exchange.
 

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It is always nice to tell what the "fix" was! Everyone learns and that can help someone in the future.
 

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Discussion Starter #8
Sorry..I'm updating on a phone and its a pain in the arse to get it through! You were correct...it was the linkage. The repair I made to the linkage was binding against the cable fitting...not allowing it to have full range of motion. I ended up flaring a tube that the cable runs through..so it would no longer bind. Thanks for the help!
 
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