Dear Tom;
Dello is a Standard Oil/Chevron product used in diesel trucks.
Most NAPA stores sell it, or you can get at 'truck stops'. Kragen may have it too.
FYI: I recently tore down a 216"(1948)for a customer. It has 133,000 orginal miles on it, with one 'valve job'. There was 1 1/2 inches of sludge in the pan. The babbit rods & insert mains are still usable & so is the cam and rocker assembly. There is almost no 'ring ridge' and I assume the pistons are good also.
Guess what; Stock air cleaner & no oil filter. This is a Sedan Delivery that delivered milk in S. Dakota.
JM......
