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Discussion Starter #1
Hello Guys, have my truck for 2 years and put around 18k miles in that timeframe the with only issue was fuel filter blockage. Two days ago a few blocks away from my house after a 2 hr drive, the truck at the stoplight had no power. Kind of thought it was in my mind and just brushed it off. The next day, had to pick up a friend from the airport 20 miles away. On the freeway truck ran normal till I hit the first stoplight. After that the truck would not shift gears and received the " range shift inhibited" error on the dash cluster with no check engine light. Limped mode all the way to pick up friend and pull off to the side to check things over. Transmission oil and everything else looked fine so call my mechanic buddy and told me to unplug batteries. It's been a one day since plugging the battery back and truck does run fine after 30 miles. At this point little hesitant to drive too far or tow/haul anything till I've sorted or find the culprit. Anyone ever just unplug battery and issue resolved itself? Search the forum and the culprit can be something simply to transmission rebuild. Any help would be great to help diagnose the issue.
 

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I'd check the NSBU switch and wiring on the side of the tranny. They are known to get crud in them and cause all sorts of issues. It's only a $60 part.

Sent from my google machine
 

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Discussion Starter #3
Thinking will keep driving locally for a bit to test and will setup a full transmission service with the NSBS and harness. Saw another thread that it could be the ignition switch Hope unplugging the battery works
 

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Limp mode is back. The battery disconnect lasted 1/2 a day or few hour drive time. During limp mode this time reverse did not engage. Disconnected battery again and drove fine. No check engine light. Going to borrow a code reader tomorrow and see if any codes
 

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Discussion Starter #5
Replaced the NSBU switch and the harness plus the ignition starter switch along with both transmission filters and oil but still in limp mode. Absolutely no codes, any suggestions to what to do next?
 

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I went through the same thing with my truck. I'd get range shift inhibited and stuck in 3rd. Changed nsbu and ignition switch and no change. I have a code reader so I just cleared codes and it would work for a little while. Took to transmission shop and they wanted to tear apart and rebuild. Luckily I waited. Replaced valve body myself based on suggestions and still limped. Turned out to be a bad shift solenoid that would only fail when it got hot enough. Shift solenoids were reused during valve body swap. Just a suggestion to look into. Took about a month of range shift inhibits to finally track down.
 
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