I have a 1994 f150 #6cil gawr 5450lb with a 2" lifted I have a 5 week can I tow a 6000lb rv

 

Do you mean a 5 speed manual?

You probably could, but you will be over payload limits and the light duty 5 speed won't last. I wouldn't do it.

 

My 94 4x4 with an auto and a straight six can hardly handle 3k empty flatbed equipment hauler. I live at altitude (8000ft) so that doesn't help, but it can only do 55-60mph with the gas pedal mashed to the floor.

6k load on the older 1/2 ton truck is really pushing it for a 6 cylinder. In fact it is even pushing it for a newer generation 150. The lastest generation is probably the only one that comes close to handling that kind of load.