With this setting i get full range in movement in both directions. BUt once i install it in the truck ofcourse i need to trim the servo since the servo arm is not sitting dead center and when it is trimmed i loose range on one of the directions.
As I mentioned the problem is the TX and its output pulse at neutral, you've verified same with your comments.
Don't these servos come from the factory calibrated to be dead on?
The servo maybe centered at 1500us but if the TX outputs 1530us at neutral the servo follows the command. As I noted earlier the programmer allows you work around the deviation at neutral realized of the TX. If the TX outputs 1500us at neutral the problem is the servo (there all typically a little off), this is common of every servo offered by any manufacturer. Only Hitec has the ability to reprogram neutral point to match the TX in use.