Grinding/scraping noise whilst driving

Hi, my jimny is making an awful grinding/ scraping noise whilst driving, sounds like a shaft is scraping against something. Is there anyway i can post a video here? The sound is coming from somewhere on the front of the vehicle. I’ve changed front drivers cv, and the shaft was fine. Changed the diff oil, no metal shavings to indicate blown diff, the noise started in 2wd also. Lockers seem to engage but I will double check by jacking it up later. 
I’m completely at a loss of what it could be

Have you checked the propshaft joints for excessive wear, with them connected there should be no vertical or horizontal movement and with them disconnected they should move freely but with a slight resistance.

Put it in 4x4, chock the back wheels and jack up the front axle. With the hubs unlocked both wheels should spin freely with no noise. If you get a noise it's most likely brakes or a wheel bearing. While you are there check the discs for any obvious scrapes or scoring.
Now engage the hubs and spin one wheel. The other should spin the other way. If you now get noise the problem is most likely the diff.
Next take it out of 4x4 and unlock the hubs. Make sure the car is securely supported on axle stands then climb underneath and manually turn the front prop. Listen for noises and look for any marks. As Lambert suggested give each joint a good shake to feel for any play.

Check for a pebble or similar jammed between disc and backing plate. I agree with Les about wheel bearings but wear in propshaft u/j's will be felt as vibration, not grinding/scraping noise.

Roger

If the movement is in a u/j, then it needs changing but even then it wont eliminate the noise you have. If the movement is in the sliding joint, then up to a point, it is normal.
Jack the front wheels and spin each in turn. If you have a mechanics stethoscope, listen for the source of any noises and report back.

Roger

Is the noise there all the time?
I have similar issue but at specific revs ( 1800 and 3200)
Its appears to be coming from the CAT

Noise from around the CAT is often a loose protection plate on the CAT. The rivets rust through

Sent from my moto g42 using Tapatalk

My initial thoughts Martin, checked all the shields whilst up on the lift but it seems to be rattling from inside the CAT as if internals are collapsing. Also thought something trapped behind shields but nothing there to be seen
But, not having any issues with power loss or consumptions and never had any warnings from sensors etc

It also went through MOT last week and the emissions are fine.

My Gen 3 started making a screeching scraping sound,like a dry gearbox bearing when accelerating (and allowing the rev counter to go past 4000)

It did it for a few weeks and I couldn't find it until one day the crankshaft pulley completely de-laminated and the outer ring fell off. I guess the noise was the outer pulley vibrating.

Worth a look at the crank pulley.