Re: 2001 Ford Ranger Squeak
Let me guess: The squeaking happen worst when the motor has been started
after sitting for a few hours? It's about the thermister in your
alternator, and your failing battery!
As the battery ages it gets minor internal shorts. So maybe a fifth of the
power stored in your battery can be lost while the truck is parked. What
remains is enough to crank even a cold engine. After cranking, the voltage
is down enough tenths of a volt that plenty of current can flow from the
alternator to the battery.
How much current an alternator produces depends on how much current is
flowing through it's field. The amount of current an alternator can
tolerate producing continually is a lot less than it can tolerate producing
for a short while. A thermistor can be used to limit how much current the
alternator produces after it becomes hot.
A battery that has been parked for a while can demand a lot of current after
cranking the engine, and a cold alternator can produce a lot. This puts an
increased mechanical load on the pulley. It slips, and you hear it.
Try bringing your belt in the house, and washing it in the sink with
whatever you use for dishes. While it dries, clean all of your pulleys with
a clean rag and rubbing alcohol. If you like belt dressing, apply it to
the belt while it is off of the vehicle, and let the dressing fully dry
before you put the belt back on. The old belt mates to the sheaves better
than a new one, a new belt might not help.
While the belt is off, check your idler bearing and water pump bearing.
If other things have you thinking about a new battery, get it now. Good
luck with your alternator pulley noise.
<firstname.lastname@example.org> wrote in message
> Hello, all.
> I have a 2001 Ford Ranger pickup with approximately 72,000 miles and
> just this past week noticed a really bad squeaking sound coming from
> the belt area.