When i turn on the truck when i put it in gear the transmission starts to **** but when the transmission gets hoti can pick up the speed to 75 mph

Assuming the tires are close to standard (i.e., 275/60/R15), this means you probably have a 4.11 ratio rear end in your Corvette. This was a very popular ratio on Chevys for drag racing. For highway driving you would want a higher speed ratio, such as a 3.55 or 3.36 ratio (or even a 3.08), depending on what is available. which would give you 70 MPH, 75 MPH, or 80 MPH at 3000 rpm.
You'll need to change the speedometer driven gear in your transmission for your speedometer to be accurate if you change the gear ratio.

there is not enough specif details available to be able to be close to exact But I will give an example that you can compare
in a manual transmission with a diff ratio of 3.909 and in 5th gear the rpms for 79 mph is 3200 rpms
the difference between gears is around 250 rpms so if you try to correlate the differences if it was in 4th gear the rpms would be around 3750 rpms so I suspect that the over drive section of the transmission is not engaging ( assuming that it is auto transmission)
so to answer your question , I am saying that it is too high in rpms for that speed and I suspect that the od is not being engaged as the rpms at 80mph I would be looking at around 3200-3500 rpms depending on the diff ratio

Bernard's Blog: Dodge Transmission Output Speed Sensor

bernardsblog.blogspot.com/.../dodge-transmission-output-speed-sensor.h...

Sep 8, 2009 - My 99 Dodge 2500 Ram won't accelerate..transmission is NOT slipping,.... It has been running fine and the check engine light even cleared itself yesterday.... So it wouldn't go into first gear and then 3 minutes later my check engine ... I have a1997 Dodge Ram 1500 with a 5.9L instead of the stock 5.2L. It ...

Dodge Ram Idle and Stalling Problems - Car Forums at Edmunds.com

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Aug 17, 2011 - 30 posts - ‎25 authors
Learn more about Dodge Ram Pickup 1500 at the Edmunds.com ... The crank sensorwas put on however it started stalling again. ... The truck starts fine, but will only runat 2000's RPM and only then if .... Then as I start driving about 1/3 of a mile go dead again, I knockout of gear, crank back up immediately.

WILL NOT GO OVER 30MPH WITH PEDLE TO METAL ...

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I WAS DRIVING FINE AND THE CAR ACTED LIKE IT GOT STUCK IN ... Then the transmission didn't want to change into 2nd gear. .... Whenever i start up my car theabs and esp light turn on and when i try driving it doesnt go over 30 mph even .... in neutral but not it just wont go up hills and i think it has something to do with

Depends if you have a regular 3 speed automatic, or a 3 speed with overdrive.
Put it in drive, it will start out in first gear, then shift into second at about 15 MPH, into third at about 30-35 MPH. With overdrive, fourth gear will kick in at about 45-55MPH.

Looks like you changed width of tire and not profile. Should/would not have made 15mph difference anyway. If you purchased vehicle new, I would suspect the road speed sensor needs to be tested. If you did not buy it new, previous owner probably had a set of large profile tires on it and changed the speedo gear/pickup assembly at the transmission.

This is what your codes mean:

Trouble Code-P0734 (A/T Additional Gear Ratio Error In Fourth Gear)


Trouble Code Conditions:
Vehicle driven to a speed of 4-37 mph at more than 500 rpm, gear selector in 4th Gear in Drive, and the PCM detected too much difference in the engine speed and output shaft speed.
Possible Causes:

• Customer may complain of intermittent 4th gear operation
  
• O/D and 2/4 pressures less than 75 psi
  
• O/D or 2/4 clutch volume indexes out of specification
  
• O/D accumulator seals are damaged
  
• Transmission enters "limp in" mode running in 4th gear
  

Trouble Code-P0735 (A/T Gear Ratio Error Fourth Prime)

Trouble Code Conditions:
Vehicle driven any forward Gear, and the TCM detected the ratio of the Input speed to the Output Speed did not match the current Gear Ratio (this test can take up to 5 minutes).
Possible Causes:

• Related Gear Ratio trouble codes may be stored (note that some of these Gear Ratio trouble codes may be intermittent)
  
• Transmission has internal problems or damage present
  

You have a transmission problem.Hope this helps, James Booth

This is what your codes mean:

Trouble Code-P0734 (A/T Additional Gear Ratio Error In Fourth Gear)

Trouble Code Conditions:
Vehicle driven to a speed of 4-37 mph at more than 500 rpm, gear selector in 4th Gear in Drive, and the PCM detected too much difference in the engine speed and output shaft speed.

Possible Causes:

• Customer may complain of intermittent 4th gear operation
  
• O/D and 2/4 pressures less than 75 psi
  
• O/D or 2/4 clutch volume indexes out of specification
  
• O/D accumulator seals are damaged
  
• Transmission enters "limp in" mode running in 4th gear
  

Trouble Code-P0735 (A/T Gear Ratio Error Fourth Prime)

Trouble Code Conditions:
Vehicle driven any forward Gear, and the TCM detected the ratio of the Input speed to the Output Speed did not match the current Gear Ratio (this test can take up to 5 minutes).

Possible Causes:

• Related Gear Ratio trouble codes may be stored (note that some of these Gear Ratio trouble codes may be intermittent)
  
• Transmission has internal problems or damage present
  

You have a transmission problem.

low on transmission fluid ,

more then likley its the speed sensor that is located on the transmission. i just had mine replaced in my pick up.

That is normal,If you do the same speed in 4th gear the rpm's will almost double.

The rpm's will repond faster in a manual than an automatic.

In a manual the engine supplies the power required directly to the gear that you have selected thus the engine rpm's will increase or decrease as needed.