2003 Chevy Impala transmission

code p0753 refers to shift solenoid(SS) A-electrical===causes--wiring--shift solenoid--ECM/TCM
The fault is electrical as it is a solenoid ( an object that has a coil wound around a core in which a bar of steel is magnetically moved when the coil is energized This bar movement moves valves or locks bands or clutches)
Change the solenoid and check out the transmission control module(TCM).
changing the oil will be good for the transmission but will not fix the electrical fault.

If the transmission is full of fluid. please go here to read the problems with the pressure control module--http://repairpal.com/transmission-pressure-control-solenoid-failure-may-cause-erratic-shifting-593, Hope this helps, chevy impala pcm may cause erratic shifting.

Dirty Valve Body
Failed Shift Solenoids
Failed Trans (internal,that is where my money is)

Sounds like worn clutches, more than likely the transmission needs rebuilt or replaced.

Sometimes the transmission sets a "hard code" that causes a hard shift from 1-2. Stop by an Auto Parts store that has an OBD scanner and reset any codes. If that doesn't work, change the tranny fluid and filter and try SeaFoam additive.
Good Luck.

Okay a few things to check first, with car off, turn key to on position but do not start, does the check engine light light up, failed bulb? run codes anyway, most chain auto stores will do for free, check transmission fluid it it dark, burnt smelling? how many miles ? when was transmission serviced if ever? did you check spark plugs are they worn out? fuel filter changed if over 50k miles could be blockage and resettles when sitting. lots of things could case this issue, i would check light and codes first.

EPC's wear out on the 4T65E trans. This always causes the intermittent harsh shifts

Have the vehicle scanned. If you have a code in the computer for maximum adapt/ long shift, replace the EPC pressure control solenoid. This a real common problem on the 4t65e transmission.

put a transmission line cooler on it

sounds like that the position cable is seizing up seek WD 40 service perhaps !!