Tacoma Phantom Squeal

How do I find that noise? It doesn’t start until the truck is moving (~18 mph), but then squeals fairly consistently, and noticeably louder when you left off the gas. Any suggestions on what it might be or how to go about locating it without taking apart everything that might squeal? Anything would be appreciated! thanks. abmanning@hotmail.com

Need more information.

Year/engine size, mileage and type of tranny (auto or standard).

Any mods done or recent repairs?

Can you isolate the area of the noise? Perhaps with an assistant?

Certainly:

2000 Toyota Tacoma
2.7 L 4 cyl
70000 miles
standard trans
No mods, no recent or major repairs

The problem with isolating the noise (i’ve been trying) is that it doesn’t start until the truck is moving faster than i could run next to it and listen and save for driving down the road slow with my friend hung under the hood, i don’t know how to isolate it.

I can say that it comes from the front end, possibly at the bottom of the engine but hard to say, and that in 4wd it seems to be a bit more pronounced. front axle? drivetrain forward of the transfer case? i thought a belt or pulley would squeal at an idle, or at least without the truck moving. would you agree? or should i check them as well? anything would be helpful, thanks for any input.