Starter sometimes won't turn over now

Maybe read the original post as to what model truck I have before hastily posting a reply? Didn't bother?

 

Update: Sorta. With all the strange circumstances regarding my starter motor sometimes starting and sometimes not, and my getting it to start fine with various things, I neglected to post that my battery is 10 years old, lol! It still may be a faulty starter relay but I'm buying a new battery tomorrow. What caused me to consider this is that I pulled into 7-11 store tonight and my headlights reflected off the store window. They seemed a little bit on the yellowish side. I apologize for not realizing the age of my battery when posting the symptoms. My bad. First things first, get myself a new battery, THEN, go from there and see if the problem persists.
10 year old AC Delco battery. I must have got a good one to last 10 yrs.

 

You certainly must have!
I pay around $100 for batteries and although they are guaranteed (for what, I don't know) for 7 to 8 years, they seldom last much over 4 years.