Help me diagnose my noise

Hi TW

long time reader first time caller

having a problem noise (under the engine and rubbing under gas pedal) when i accelerate i hear deep gurgling/rubbing noise. speeding up to 50mph at 2000 rpm there is no noise until the rpm drops to ~1400 also hear it as im coasting ~20mph and rpm is ~1100. foot off gas no noise but pressing gas at 45-50mph @1400 rpm is sounding off. Shifting to 4th gear is noiseless but louder in 4x4 5th gear.

wheel bearings are good
serp belt changed
differentials were serviced
center shaft bearing replaced

my last guess is the needle roller bearing (no lift)
anything else it could be?

thank you