Just had my 1982 chev 6.2L diesel rebuilt. The original 1982 truck manual says standard 30 weight oil. Would you use that or 15-40 Delo or equivalent?
Thanks

 

Use the 15-40 and imho you really want to use Rotella, first number in 15-40 means it is a start up like a 15 weight but the 40 is the important number.

I had a 1984 CUCV it called for the 30 weight but all that had been put in it for the last 20 years was Rotella 15-40 and it's still on the road.

 

Thanks for the info. appreciate the help.