The Washer : HA 806 Ser. 769638SY
Born Nov, 1973
The HOH Dryer :HDE 806 Ser. 405342 SU
Born Sept, 1973
I felt the belts this morning and they feel loose, so may as well change them Right?
The pump belt should naturally feel kinda loose when properly adjusted. Maytag specifically designed it that way. It would definitely be a good idea to replace both belts since you don't know the history of the machine.
And IIRC, they are self tensioning.
The transmission belt is self-tensioned by the two motor carriage springs. The pump belt is tensioned manually by loosening the 3 bolts that hold down the pump and shifting the pump left/right in the slotted grooves for desired tension.
Speaking of motor carriage springs and glides (rollers for the older machines), it would be a good idea to replace those too. Every Maytag I have acquired had very worn (original) rollers, weak springs, and were dry from the lack of poly lube, which caused erratic operation. The square glides superseded the rollers, but they're backwards compatible.