HIgh Revolution while driving

Did you test electrical circuit's before replacing the sensors ? Do you know how they work , where battery voltage comes from ? May only be 5 volt ref. voltage from the transmission control module .
DTC P0720 VEHICLE SPEED SENSOR·A/T (REVOLUTION SENSOR) Revision: May 2004 2003 Sentra TERMINALS AND REFERENCE VALUE MEASURED BETWEEN EACH TERMINAL AND GROUND Diagnostic Procedure ECS005X0 1. CHECK INPUT SIGNAL (WITH CONSULT-II) With CONSULT-II 1. Start engine. 2. Select "TCM INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II. 3. Read out the value of "VHCL/S SE·A/T" while driving. Check the value changes according to driving speed. OK or NG OK >> GO TO 3. NG >> GO TO 2. 2. CHECK REVOLUTION SENSOR (WITH CONSULT-II) With CONSULT-II 1. Start engine. - Check harness for short or open between TCM, ECM and revolution sensor. Refer to AT-129, "Wiring Diagram - AT - VSSA/T" . - Check harness for short or open between ignition switch and revolution sensor. OK or NG OK >> GO TO 3. NG >> Repair or replace damaged parts. TERMINAL WIRE COLOR ITEM CONDITION DATA (DC) 10 BR/R POWER SOURCE WHEN TURNING IGNITION SWITCH TO "ON" BATTERY VOLTAGE WHEN TURNING IGNITION SWITCH TO "OFF" 0V 29 W REVOLUTION SENSOR WHEN MOVING AT 20 KM/H (12 MPH). USE CONSULT-II PULSE FREQUENCY MEASURING FUNCTION 150 Hz 42 B/W THROTTLE POSITION SENSOR (GROUND) - 0V

https://www.nicoclub.com/FSM/Sentra/2003_Sentra/at.pdf
Look it up in factory service repair manual

Putting different tyres on will alter the accuracy of the speedo and the recording of distance, so I wouldn't pay much attention the fuel economy. For example, a single revolution of the axle will remain constant regardless of the wheel size, but the revolution of the wheel versus distance traveled will vary depending on the diameter of the tyre fitted. If the new tyre was, say 10 cms circumference larger, then the car will travel 10cms further each full revolution (that is 100 meters every 1000 turns. If your speedo sensor is determined by the number of revolutions of the axle, then every 10,000 turns you will have travelled a kilometer more than with the old tyre size (less if the circumference is smaller). The figures you give convert to (UK) 25 mpg dropping to 20 mpg with the new tyres. Does seem poor consumption figures for a small car, but if a big engined truck that might be acceptable. All depends on how you drive it as well.

Overdrive is used for better fuel economy on the highway. You have different gear ratios for each gear, for example 1st would be 4.6:1, second 3.2:1 etc. this means for every 4.6 revolutions in, you have 1 revolution out (of you transmission). A overdrive gear will have a ratio of greater to 1:1 (i.e 1:1.6) mean the output is more than the input. This would give you a higher speed at a given RPM, or a lower RPm at a given speed, thus more fuel economy.

The throttle position sensor needs to be replaced.

check throttle position sensor,check cables for sticking

Give some more details of the problem.

Hi! i have a 2002 nissan altima(3.5 with automatic transmission). i just got the same codes today. i had 2 different nissan technicians check my car. and they told me it's the revolution speed sensor. After 30 min. of use my car revs high until 8,000 rpm and stays on the same gear for a full 5 seconds or more, then changes to the next gear harshly!! sometimes it just won't change gears and i have to stop in the middle of a highway or avenue. lol!!! when i brake to a complete stop, the transmission slips. does this happen to you? good luck, bro!

the car is heated at low speed because less air flows at high speed and does not heat because the air flows more, check if the fan is turning on and check if you have good revolution,, check fuses, check the thermostat temperature, clean radiator use antifreeze coolant and finally check the pulley on the water pump with its setting correct ajustment. and finally if you work on the motor over time, verify that the ignition times are in place,

sounds like the problem is brake related. That ticking you're hearing is your front brake rotors, clicking against the sides of the brake caliper. As you speed up, the clicking will get faster untill you won't be able to hear it, (it's still there, it's just inaudible at such a rapid revolution) upon deceleration, you will notice it more prominently, clicking in rhythm to the speed of your wheel's revolution.
basically, It indicates your brake pads are worn down. Unfortunately the condition will get worse, louder, and the car will become extraordinarily more dangerous to drive as front braking will be compromised if the vehicle's braking conditions persist.
A qualified mechanic will setup the brakes, rotors, check for warpage, hone the rotors if need be, and be able to install a proper replacement pad.