Re: Oil Weight for 1951 288 that had rebuild 20-25 years ago

Posted by Tim Cole On 2022/9/1 18:36:46

Packard specified 20 weight oil, so 10w-30 should be fine. I assume they recommended racing oil because of the higher zinc content. Risolone offers an additive which might be cheaper than racing oil if you want the high zinc. Heavy oils serve mostly to rob horsepower via taxing the oil pump. I don't know if the valve springs in a 70 year old Packard are strong enough to benefit from the zinc.

My lawnmower specifies 30w oil and I buy the B&S oil only because the engine doesn't have a liner and I haven't checked what is in the stuff.

I do recommend dropping the oil pan because oil filters were an option. Or you can buy a borescope from Harbor Freight and inspect it that way via the oil fill hole.