Re: 1938 Packard Hearse - HELP PLEASE!!!!!!!!!!!

Posted by Rusty O\'Toole On 2008/8/7 7:35:28

When did Chrysler recommend 50 weight oil? I have Chrysler owner's manuals back to 1951 and the only thing they recommend 50 weight for is the oil bath air filter.

They recommend 10W oil for cold weather. They also recommended multi grade oils and detergent oils as soon as they became available.

10W30 is a good all around oil. For your climate 20W50 may be all right too.

25 -35 centigrade is only 75 to 85 fahrenheit. Hot enough to be sure, but not hot enough to cook your motor.

Use 10W30 if your motor is in good shape. If the bearings are worn and oil pressure low, 20W50 will bring up the pressure.

I don't have a Packard manual but my Chrysler manual recommends SAE 30 for all temps above freezing. As soon as multi grade oils became available they changed this to 10W30.

This is for a flathead inline engine similar to yours. I'm sure the Packard experts will chime in if Packards are significantly different.

There is a lot of hokum out there about old cars "needing" some inferior grade of thick oil. Baloney. Multi grade and detergent oils have been around since 1947. If your car was made since that time, chances are it has never used anything else.

In the case of your 1938 model it is likely the garage man or owner has been using multi grade detergent oil for the last 50 years.

Now that you have had the pan off and cleaned it out there is no harm in running detergent oil. Not that there would have been anyway.