Ive found the same as you Danny  I use 4.5 ltr [ around  5 quarts] when I do my oil and filter, Pretty sure if I put more in it will leak more ; )



"Came too close to dying to stop living now!"

The 1 1/8” oil drain plug size is correct for a 1956 Ford.
 
With an oil filter change, add six quarts of oil and then run.  After shutting off the engine and allowing the oil to drain down for 3-5 minutes, mark the existing dipstick with a new full mark.  The other option is to replace the existing dipstick with the correct diptick tube and dipstick combination.  The owners manual for a 1956 Ford will also tell you six quarts of oil with a filter change.

Lorena, Texas (South of Waco)

A possibility is the workshop manual is incorrect, there were lots of mistakes in the manuals. I can't recall what mine takes but I normally put in close to what should be normal then check the dipstick and top up until it is full.

I have a 1956 Ford with 292 yblock and had the oil changed (about twice a year) whenever I brought the car in for other service. I use Castrol GTX 20W50 and a Motorcraft FL-1A oil filter. So yesterday, I decided to change the oil myself for the first time. My first surprise was that the oil pan plug was had an 1-1/8 inch head. Is this the stock plug size?
The shop manual oil capacity for the 292 is 5 quarts without a filter change and 1 quart more with a filter change for a total of 6 quarts. I took the cap off of the oil fill tube and I took the plug out and let the oil drain about 30 - 40 minutes and reinstalled the plug. I then removed the oil filter and installed the new one. I put in exactly 5.5 quarts of oil in and ran the engine for a few minutes and checked the level. I was surprised that the level showed approximately 1 quart high. I let it set overnite and checked it again and it was still 1 quart high. I took it for a 10 mile run and rechecked the level and it is still 1 quart high.

I thought of 2 possible explanations: 1. Somehow approximately 1 quart of oil is somehow trapped in the engine or 2. My dip stick is not stock. I measured the dip stick and it measures 25 inches from the tapered tip to the cap. Is this the correct length for the stock dip stick. Any ideas how 1 quart of oil would not drain out of the engine? I know I should have measured the amount oil that drained but disposed of it before I put the new oil in. Should I drain oil out or run it like it is?

Thanks in advance,
Danny