I bought a 2004 heritage V6 Transmission was bad my father in law rebuilt it (he is a retired Ford Transmission guy) in drive it will not shift out of low if you take off in 2nd it will shift out of low on a rare occasion the OD light on the shifter will start blinking and it will shift fine does anyone have some ideas?

 

I have an idea. Get the codes read so that you know what's causing the problem. The places that read codes free CANNOT read these codes. You need either a good independent shop or a Ford dealer.

 

You need a scanner to get the codes. a simple code scanner will not get them. In other words I agree with Mark above^^^^^^