Help!

[simpleboyy]

Hey guys i got a problem, i just changed my gear box oil about 2 days ago and used the nulon 75w90 semi-synthetic and that G70 as well

and the gear changes got worst i put in about 3.5 letres and it got worst but 5th gear feels smooth but gears 2 3 and 4 all crunch not as bad but its noticable and annoying that fact that its cruching but gearing down is very easy oh and the thing was that after every outing the car went i come back home or stop some where i smell gear box oil burn.

the nulon oils are they really crap or somthing? is their any oils out their that arnt too expensive but works please help me!!!!