I have random metal rotation noise that seems to come from front left of jeep, starts and stops a few times when accelerating only between 0-40km then stops or appears to at any speed above. Thought it might dust cover behind rotor rubbing, not that, just got new front axel u joints so not that. Any suggestions?

 

Possible Wheel bearing?? If it were mine I'd jack the front end up, and spin the tires and see if you can hear it. If you can't i would take the tires off and spin the hubs and take a screw driver and put it on the "c's", axle tubes and steering components while the screwdriver handle is up against you ear and have someone spin and turn the hubs you may be able to hear it...it works great for a free stethoscope! ..i always use it to find barely audible noises...it may help you pinpoint the issue

 

I like the idea of screw driver to hear noise, will have to try that, that being said I tried rotating with tire off and could not hear noise and there does not appear to be any rattle