Oil for 1971 Chevelle Malibu

[Benoit]

A friend of mine own a nice Chevy Chevelle Malibu 1971. The car was rebuilt in early 2000 and the previous owner has installed an engine from a 69 Chevy pick-up. It is a v8 5.7l 350.

Amsoil as just release a new oil, the Z-ROD 10w30 Synthetic Motor Oil. Amsoil Z-Rod 10w30
We would like to know if this oil will be safe to use on his engine combine.

He is now running Castrol GTX 10w30 since he own the car in 2006 but with 70,000 miles on the engine, He want to put something better to keep his engine life as long as possible.

He use the car on summer time, from May to octobre and then he store the car from November to April.

 

[Gene K]

While the Z-Rod is likely an excellent lube for a flat tappet engine I see no reason to change what he has been doing. With 40+ year old seals I wouldnt temp fate and at this point I doubt a change in lubricant will significantly change the lifespan of the cam.

Run it until the engine dies (if it ever does) then either build it or replace it with a crate motor.

 

[Pablo]

Is the engine rebuilt? A truck engine - is it stock? More information. What is the valve train?

It could be argued that your current oil choice is indeed not the best, but without more info on the engine, it's just speculation.