no overdrive??

[fontana01]

I have a 2000 xlt 4r44e at 65 mph I'm turning 3200 rpm. I count the shifts and it seems to be locking up in overdrive. But when I turn off overdrive with button the trans does not down shift. The truck is all stock with 8.8" rear end. I'll check rear end tag for gear ratio in the morning. I think if truck is factory low geared it should still Cruz at a lower rpm.
I just bought truck as a commuter so please help with any info so I can get better fuel milage right now it is horrible.

Thanks in advace