I'm on my first GM with the serpentine belt. 89 S-10 Blazer, with 260K
miles. I've had to replace the idler (plastic pulley, just disappeared one
day) and the spring loaded tensioner.
When I replaced the idler, I took the junkyard unit apart, and relubed it.
Can't remember what I used. The tensioner locked up, and was squealing and
being awful. The replacement didn't look much like the one I took off, but
it has been working nicely. I oiled that one, also.
Just one man's experiences, but it's consistent with what you're seeing.
Them things lock up, and make a mess.
Christopher A. Young
Do good work.
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