1996 240sx grinding

[FDNiss240sx]

Hi guys i have this grinding noise from first to second gear, but it only happens when i shift above 2500 rpm's, and from second to third above 3700 rpm's could this be my clutch? or something worst like the transmission?i'm just asking this because i'm sure somebody when thru the same problem and you guys know a lot more then me

BTW the clutch is like a year old with like 8000 miles

[MaximA32]

Have you searched at all?

[FDNiss240sx]

I did and as soon a get my friends garage free, i'm going to change the cylinders to start with