5w-40 weight oil ... dumb question

[Powerzen2002]

My car is a 90 (240sx) with 75,000 miles.

I have a slow leak in my valve seals that cause me to burn oil
at higher rpms. ANYWAY, I normally use 10w-40 ... engine holds oil a hell of a lot long than with 10w-30.

I dont like the way the car drives on 10w-40, (feels sluggish).
Would 5w-40 be any better? Or is my mileage to high and car to old for the higher volisity of the 5w oil.

I know they say that 5w-30 is great for these cars (and many new cars .. ) but i dont think so on a 12-13 yr old car.

P.S. anybody know a good mechanic who works cheap and will be willing to fix my valve seals at a good price? hehe


Thanks!