Yuri -- Thank you so much for your help -- you sound like you are an old pro. I will take your advise. I thought about last year when they put in a new fan -- and you are right, crazy money. I bought a second one this year because when I noticed the heat was not working the furnace had been trying to cycle on all night. By the time I discovered the blower motor was super hot! My assumption was that it was locked again, so I bought a new one with observed results as I have explained.
A new furnace is in order -- hopefully I will have a few good days to try and seal up the furnace room before I install it. Last question -- have you had any luck with Carrier? -- I found some 80% on sale (overstock for $500).
Yours is a 92% efficient. The 80% is mid efficient and needs a chimney. For $500 it is "freight damaged" LOL. I have seen a LOT of different units in my 31 yrs. Lennox is my favorite, Rheem is a good basic furnace IMO. The most important part is to get a reputable dealer to install a good well established brand name unit. Lots of "rebranding" these days and hard to get parts for them later. L and R don't do that or have that "problem".