Technical Amount of oil 347 Poncho

Hey guys,

My 1957 Pontiac with a 347 needs fresh oil and filter. Does somebody know the amount of engine oil? ATM he runs with 15w40 but somebody told me that 20w50 is the better Deal? Whats your opinion?

Kind regards,

Torsten

 

My Motor manual shows that the 1957 347 engine requires 5 quarts of engine oil plus 1 for the filter (6 quarts total). The specified grades are 20W (10° to 110°F) and 10W (-10° to 95°F). The normal oil pressure is 35-45 psi.

I would use a 30-grade (0W-30, 5W-30, 10W-30, 15W-30) Heavy Duty Engine Oil rather than 15W-40. The oil pressure relief valve will bleed off excessive pressure from thick oils back to the sump and less will end up in the bearings. See Engine Wear.

 

My Ford yblock didn't specify a detergent oil.. ruined most of them. I prefer 10-30 in older cars, we don't drive them much and a 50 anything is just too thick unless it's worn out especially if they never get hot.

 

Run 10w30w and you will be just fine. I ran that back in the 70's in a 57 Pontiac. With Valvoline oil the engine was quiet, with 1 qt of Pennzoil the lifters would start clattering. Change the oil back to Valvoline and quiet again.

 

30 wt was always fine for me. Don't recall 10/30 in the 70's. Later on I recall 10/40.

Realistically anything you use today, is going to be better than what was around when that engine was new.

Heavier weight oil is a mask/bandaid for a tired engine...sure, some racing engines need it, but do you?

 

I run 6 Quarts of 20/50 in my '57 Pontiac with the original 347.
That is with the filter change.
I change it once a year since I only put about 2500 miles on it.
I have put over 40,000 miles on it in 34 years.
KK