if you remove the egr vacuum hose so it dosen't work will it hurt anything, would you gain anything from doing this if it was working properly before. truck is 90 w150 with 318

 

your ignition timing is already advanced to compensate for the EGR
and if you remove it you may need to use higher octane
when in the 40 to 80% open throttle range.

EGR is not used at full throttle, so no effect on maximum horsepower

If your sparkplugs and ignition is in good shape
EGR improves MPG.

If your sparkplugs and ignition has a problem
EGR increases mis-fires and decreases MPG.