Hi all,
My 1991 2wd 22re (226k miles) has developed a new sound over the last week. It's difficult for me to diagnose because it only happens when the truck is moving.
It's a low sound -- a growling or a warbling sound -- and it doesn't seem to be synched to engine rpm or even the speed of the truck.
As soon as the truck stops, it will go another maybe second and a half and then stop.
I don't think it's a wheel bearing; it doesn't sound like a wheel bearing.
I am leaning toward a pulley or the alternator. Or maybe even a loose belt.
Just thought I'd throw this out here in case anyone might know *exactly* what that sound is before I start down many (proverbial) roads.
Thanks very much,
Andy

 

Found it!
Was the breather tube disconnected from the air filter box.
No idea how it fell out of there, but it's old like me.
Am glad of simple solutions.

 

PCV or PAIR system. I am leaning towards pair because of the description of the sound.