A farm I work on the '94 Pickup with the 3.0 V6 and 5 spd manual transmission.
Engine runs great, but when driving: pushing the throttle down to about halfway produces normal power, a throttle pushed beyond halfway produces a loss in power and what feels like a rough transmission and what sounds like a different exhaust. Let off the gas a bit, and it runs okay again. This makes climbing hills and being under load pretty difficult!

The O/D light flashes in the dash, and when the diagnostic port is jumped: O/D Flash Codes 62,63,64. Check engine flashes constantly so the V6 seems it's in good condition. Quick internet research shows these O/D codes are intended for an automatic transmission, and points to solenoids having bad connections. So:

Are there solenoids in a manual transmission? Where?
Would any of these codes explain the throttling issue for a manual transmission?

Any help or advice is much appreciated you guys!!!!

 

Someone swapped in a manual in what was originally an auto trans truck. Look at the door sticker should say A340 on there meaning auto trans. Those codes only refer to your solenoid that you don't have so you can ignore them. Most guys pull the dash light out. That isn't causing your bogging issue though. I would do a normal tune up ngk vpower plugs denso wires and rotor and the air cleaner. If that doesn't help check your throttle position sensor.