Starting Issues - 1997 Ford Expedition

I have a '97 Ford Expedition with 165k miles and about a month ago I started having occassional (maybe once every 20 starts) starting issues. I crank the key and just hear one click and nothing else. It ususally starts on the second or third try, however, just the other day it took about 30 attempts to start. Each failed attempt is the same…one click and nothing else. It has spent a day in two different shops, a local mechanic and the Ford dealer. Neither was able to replicate the problem and could not do anything about it. The mechanic replaced the terminal ends on the battery and both tested the starter circuit and found no problems. A new starter costs about $350 so both are hesitant to replace the starter, as they say it could be other things (resistance?). Now, Iam in quite a pickle, as I would be more than willing to pay the $350 to fix the problem, however, no one knows if that will fix it. At the same time, I can’t just do nothing, as although it has eventually always started, I am concerned about getting stuck somewhere or just flat out being embarrased by my old '97 friend in the wrong place. The dealer talked about the pinion. In any case, what should I do? Should I suck it up and replace the starter and just hope that is the problem? Or, is there another possible cause? I HAVE to do something. This board is great for a know nothing like me. I always get back such knowledgable responses and very much appreciate them all. Thanks.

This isn’t rocket science. Have them measure the current draw to the starter while attempting to start the engine. If it’s over spec, then there’s either a problem with the starter or with the engine itself. If the current draw isn’t over spec, there’s nothing wrong with the starter.