Do Not Shift Light??

[Bad340fish]

I noticed this awhile ago. On my work truck which is a 97 INT with a DT466E motor and a Spicer 6+ trans. It has a DO NOT SHIFT LIGHT. You can see it in the dash lights when the sun shines on it just right. Any idea when this would come into play?? I have never seen it come on no matter what conditions I am in. The truck is on the heavy side 35K and 210HP. So its at 100% workload 90& of the time. I figured the light might come on when it senses that it can no longer pull any RPM. Most any incline requires wide open throttle at around 2400RPM to maintain any kind of speed. I assumed the light would come on in a situation like this. Just thought I would throw this out there to see if anyone has ever heard of it.

Clark

 

[tgbol]

The do not shift light is used in conjunction with a electronic controlled Allison transmission. If the electronics go into the limp home mode the light comes. The trans will remain in the gear it was in when the light coame on. If you shift the gear then the trans goes into neutral and the big hook comes to get you. If you are using the PTO when the light comes on it is also big hook time.

 

[illflem]

My '95 3500 5 speed has up and down shift lights listed as an option in the owners manual. The light is located next to the wait to start light.