Allison 5sp: Help! Shift Range Inhibited

[darkone98]

I was backing out of my driveway this morning, and when I went to put it in drive, I gave it throttle and it acted like it was in neutral, now I cannot get the truck to move at all. I tried to change gears and shift range inhibited came up. No codes on my edge insight, and transmission fluid looks fine and is properly filled. I'm really hoping it's the NSBU, but when I go from reverse to park, I hear a loud clicking, is this typical of a switch?

 

[Mike L.]

Hook up a real scanner and read codes before you throw money at it.

 

[THEFERMANATOR]

Hook up a real scanner and read codes before you throw money at it.

What he said. Probably 90% of the scanners out there cannot read TCM codes. Shift range inhibited should definately throw a code. And since your sig says you have an 05, those NSBU's don't go out very often.

 

[darkone98]

I guess I won't need one now, my transfer case was on its way out and has finally piled up, shifted it into 4 low and everything went back to normal. Gonna pull that sucker today, Thanks for your help!

 

[Mike L.]

Transfer case problem can cause range shift inhibit problems. Remember the output speed sensor is in the T/C, but the TCM doesn't know that.

 

[onedirtymax]

Not to hijack your thread but I am having the save problem but mine only says "range shift inhibited" in 4lo and in reverse. It feels like its jumping out of gear and I can go to neutral and then back to reverse and its fine for just a few seconds. Any suggestions guys?

 

[THEFERMANATOR]

Not to hijack your thread but I am having the save problem but mine only says "range shift inhibited" in 4lo and in reverse. It feels like its jumping out of gear and I can go to neutral and then back to reverse and its fine for just a few seconds. Any suggestions guys?

Pull the transfer case out and chances are you will find the nylons on the shift forks are gone.

 

[darkone98]

I got a good deal on my case, I pulled it myself and only paid $400 used from a burnt up LBZ. Looks like my decision to drive it after 4 Hi went out turned out to be a bad one, because something let loose in there and punched a large hole in the upper passenger side where the chain was. Put in 2L of 5w30 and am back in business.

 

[THEFERMANATOR]

I got a good deal on my case, I pulled it myself and only paid $400 used from a burnt up LBZ. Looks like my decision to drive it after 4 Hi went out turned out to be a bad one, because something let loose in there and punched a large hole in the upper passenger side where the chain was. Put in 2L of 5w30 and am back in business.

Hope you did a pump rub kit so you don't have this happen again.