Chrysler Repair: Automatic belt tensioner, 3.3L van, drive belts, splash shield

Question
Have 93 Chrysler T&C minivan 3.3 engine. Need to put on automatic belt tensioner.  Would it be best to go through the engine from the top or from the bottom to take it off?  Are there any parts that need to be taken off also and if so, could you describe them?  What I have is a squeaking or sqealing noise when the van is running. Just put a new serpentine belt on when the other broke (van does have over 210,000 miles by the way).  When I checked with an area mechanic about this noise and what was causing it, first he put a lubricant on the belt (I didn't approve but he was the mechanic so I figured he knew what he was doing!) causing it to slide off.  He put it back on but now I find the van is also running hot at times.  He was the one advising the belt tensioner was old, the belt was loose as a result and this needed to be replaced (tensioner pulley that is.)  Also can you think of anything that would cause this squealing or squeaking noise beyond the tensioner pulley?  Thanks in advance.

Answer
Hi Sheila,
Another reason for belt noise is that the tensioner is not only weak but also either not in the same plane as the other pulleys or that it is tilted relative to the plane of the belt, either of which is what will cause noise. So replace the tensioner first and see if that solves the problem. If not, then visually check whether all the components driven by the belt are in the same plane, and if not adjust the one that seems most out of alignment.
The best way to access the belt and the tensioner is to jack up the right front, remove the wheel, and then notice that there is a removable splash shield between the wheel well and the engine compartment area which keeps water from reaching the drive belts from the road when it is wet. Once you remove the splash shield it should be good access to the tensioner for its replacement.
Roland