Motor oil for an original motor?
 

Hello all!
I am trying to figure out what type oil would be best for a unrestored DZ 302 engine. The engine just turned 78k miles. Right now I am using Shell Rotella SAE 30. I have read on some other post that the zinc is needed. Maybe I am using the correct brand of oil but what about the weight? I obviously want what is best for a old engine that has not been over hauled.
The car is driven by the way.....

Also, how about trans an rearend fluid? What do you recommend?


Thanks for the help!!!!!!!!! https://www.yenko.net/ubbthreads/imag...lins/beers.gif

Re: Motor oil for an original motor?
 

I use Rotella-T in my Z and also in my survivor SS nova. I believe that some of the experts don't recommend any synthetic for the rear or trans. I use any good 85-90 in the trans and rear. I use 15w40 Rotell-T in the Z and the nova. You can also use some of that GM posi fluid if you want. https://www.yenko.net/ubbthreads/imag...lins/dunno.gif

Re: Motor oil for an original motor?
 

My 70Z is a 57K mile, unrebuilt engine. I run GTX in it, but Rotella should also be fine.

The main concern with the lack of zinc in today's oils is with cam break-in, which obviously isnt an issue with your car.

For the trans and rear, good old 80-90 gear oil will be fine.