My 1997 F-150 makes a loud squeeling/squeeking when the engine is under compression, like going downhill in first gear. If I push on gas pedal sound completely stops. If I back up sound is also there, especially backing uphill. I checked u-joints for play and checked rear axles. Sound seems to come from middle area of truck. Any suggestions?

 

What engine and transmission?

 

2wd, 4wd, what? Probably a u-joint as you really can't check them 100% on the vehicle. Could be a throughout bearing, -if manual, but I doubt it.

Check all your fluids.

 

True - I had squeaky u-joints but they felt tight.

 

Its a 4.6 with a 4r70w transmission. Hopefully just a u-joint, but im worried that it is transmission problem. 172,000 miles on truck, with original u-joints.

 

If the u-joints are original, I'm betting that they are dry.