2.5 d King cab knocking/grinding noise

Hi Guys

I need some help please, before i get ripped off at next service....for the last week i have noticed a funny deep knocking/grinding sound coming from my engine. I can clearly hear it inside the vehicle, but once i am listening for it at the engine i cant hear anything. After I start the vehicle this noise starts, but seems like after the idle has settled its gone. But as i step on the gas the sound starts again. Even if i switch on my aircon the sound starts again. So clearly linked to revs picking up. If anyone possibly knows what this can be i would appreciate it very much bofore i get told to replace various parts that weren't necessary.

Regards
Ossie

Manual or auto ?

Sorry it is manual 4x2

Could be a thrust baring , try listening around the trans tunnel , and using the clutch and see if the noise changes

and its going for its 105000kms service

well its around that time the clutch could give issues

Even when i engage my clutch, noise stays the same.

well see what others on here have to say , i picked on one of the cheaper options , what ever the mechanic says , if its nasty call around and get other prices , the buggers think that once its in their garage the jobs theirs

Tnx Steve1961