My vehicle speed is higher than my speedo.

Of course the first thing was to change out the Vehicle Speed Sensor. Same issue. 15-20 mph difference between the truck and speedometer using a GPS on my phone.

Pulled out the pinion gear for the speedo at the transmission tail housing (1994 dodge ram 2500 automatic 47RE)

Looked at the gear. Gear was green, and looked almost new. Reinstalled gear, and made sure to index it correctly. No change in speed.

Checked automatic transmission fluid making sure it was at recommend level.

So where do i go from here?

Bad speedo cluster?

OD locks up still at 45mph according to my gps.

And kicks down when I floor it...

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