7.3L not starting

[RossWM]

so i went to work yesterday the truck was running fine and when i got off it wouldnt start, i had some trouble starting it in the cold before so i replaced the glow plugs and glow plug relay and its been running fine till now. I tried using starter fluid and couldnt get it to start but it sounds like it was having trouble turning over like the battery was dead so i tried to jump it, no luck
i've always had to crank it and unusual amount of time to start it so i'm thinking my starter has gone bad, does this sound like the most likely problem?

[jesilvas]

Starter Fluid !
Check batteries, cables, connections, starter.
And I'd double check the GP and GPR for proper operation. Just cause it's new don't mean squat.

[RossWM]

it was the starter i took the starter to advanced they tested it and told me it was good but i went ahead and got a new one anyway and it fired right up.