Transmission thump at 50-60

[firestarter]

So, ever since I pulled a u-haul across the country in Drive (the strange 3-4 combo) I've had this odd feeling with the transmission when it's trying to decide whether or not to shift from 3-to-Drive (or visa-versa i should say). Basically, when going up hill around 55 it decides to downshift and slams down to 3rd or maybe 2nd in some cases (55-35 in 1sec flat), it's a very rough abrupt "hammering" feeling and afterwords it seems to mess up the fuel sensor (gas gauge reads that i'm sucking down gas like no other when i'm not). Once the vehicle is restarted the gauge reads just fine.

I stopped by a local shop and they said the transmission timing sensors are probably out of wack and it takes a computer to restore them?

Does this make any sense? Have others had this issue? If there's a way to fix it without shelling out for a re-program of the computer i'm all for it.

Thanks in advance,

 

[firestarter]

So after looking around some relate the issue to a bad wire within the speed sensor. Where would I be able to find the speed sensor?

Any information on installation of the sensor would be great.

Thanks in advance,