Come to a stop sign, idling about 700 rpm. Put my foot in the gas to go slightly faster than what would be considered normal driving which brings the RPMs right up to about 2000, 2100. But there the RPMs stay. Between about 9 or 10 mph and 30, 35, 40 mph, which is what I usually am doing around town, the needle doesn't even move. Kinda like I have a continuously variable tranny. I assure you, it's a 700R4. I know work has been done to transmission, is this how a higher-stall torque converter behaves? My tach works just fine. It's not exactly "perfect", but it works just as perfect as you can expect any stock tach to work.

 

Maybe the convertor locked up accidentally, and the RPM spread was so small you didnt notice it climbing.