not shifting

What do you have? Oher than "a truck"

Gauges inoperable are probably the cluster.

97 chevy 3/4 ton, 5.7, 4l80 transmission

I may not be of much help, but others may jump in. Does the loss of the speedo happen concurantly with the shifting problem? Or is the shifting problem always present?
I may be wrong but I "think" the speed sensors that go out of range are ignored by the module, over riding a shifting problem. If there was a speed sensor problem and you have abs, the abs light should come on.

How often have you replaced the transmission filter?

i just put a new fliter in along with a tcc circut and and shift solanoids. it dont shift at all , it stays in first. now sometimes it will shift and thats when the insterments stop working, and when the insterments stop working, thats when it kicks in and out of gear.
but most of the time the interments will work but will not shift.

I was talking to a tranny guy the other day on similiar symptoms but it was a caravan. He remarked about a bad input/output sensor,but seems to fit since there is a relationship to each other on the symptoms.

I looked around on Google, I didn't realized these are forms of speed sensors. :oops: When I thought of speed sensors, I automatically thought wheel speed sensors.

That's a Service Writer for you! :)