I have a 2002 Jeep Grand Cherokee (4x4). There is a high pitched noise that is coming from someplace in the engine in front of the driver area. It almost sounds like a high pitched sound like when you have an ungrounded radio...but its not it. It does not happen all the time, but when it happens, it is when I start to drive above 40 mph. If I press on the accelerator, it will lower pitch. If I let off it, the pitch increases. It does not happen if I put the vehicle in neutral. Of course I can never reproduce it for my mechanic and he has no idea. Please help, it drives my sensitive ears crazy!
I'm not sure if I have the same issue but with my grand cherokee if I'm in 3rd gear doing about 40mph and the torque converter locks up I get the same noise you are describing and it changes with my throttle position. Same thing in 4th gear around 55-60 mph when the converter is locked up. I know this doesn't answer your question but if it is the same problem I have then it most likely has to do with your torque converter. Hope this gives you somewhere to start looking.
2003 WJ Laredo 4.0 I6 with Selec-Trac, 4” BDS lift with 32” Goodyear wrangler Duratracs, KC Slimlites mounted on Kevin’s Offroad Light Bar, Rusty’s Recovery Hooks and T-Case Skid, Midland CB,(Daily Driver)
1994 YJ With 30” Interco TSLs (Project Jeep)
theres been a few threads ill find a link for you. however, ive driven my WJ for 2 years and its made this noise. nothing has broken? why fix it?
does it sound like a stuck pig/ dying goat squealing noise? lol, ill find the thread, one guy said it was a wheel bearing/hub assembly. ive heard it was a pinion bearing issue. i just say, drive on it till it breaks and youll know whats wrong with it!
98 XJ- 4.0L, NP231, AW4, chryco 8.25, 4.5" mid arm 3-link, 285/75 Herc terra tracs on moabs, V8 ZJ tie rod, fabbed bumpers...
No, the sound is even higher pitched. Upper frequency. It almost sounds like it is coming from behind the dash but if you roll down the window, you can hear it louder. It must be coming from the engine compartment on the driver's side.