Rumble when turning,condensation under truck,starter

What a great site. Tight budget has made it necessary for me to do my own maint. on my truck.
I found out that the sticking starter on my dodge ram is an ongoing problem from this site, and yes i burned up a fuel shut off switch,ouch.
truck has 160k on it, should i just replace the contacts and plunger on the starter as recommended or replace the whole starter?
Also, had new all season tires put on truck with siping, and get a low hum when making turns, is this the tires or a bearing going out. With winter here I have been using the heater and notice a small plate size water spot on the driveway under the passenger side dash board that as near as i can tell is condensation from the heater. The stock insulation around or near the heater is damp...is this normal or baaad news.
Thanks for your time.eb

Shot heater core.

Replace the whole starter, don't be a fool.

Yea, i'd replaced the entire starter. I mean, hell whats the use of fixing the old one when you can buy an entire new one with a warranty?