Hot Rods 1959 GMC pickup 270ci engine oil capacity

My 59 GMC 270ci engine has a dipstick that appears to have it's oil dipstick shortened and a new line scribed above the full mark on the stick. The oil level has been at that mark with good pressure and no issues.
I have searched the web for the correct oil capacity and came up with 8 quarts plus
1 1/2 quarts for a stock filter.
Today I did an oil change. I have a remote aftermarket spin on filter that takes less than 1 quart. I added a total of 7 quarts and that brought the level up to slightly above the scribed line. I am afraid to add another 1 or 2 quarts.
Anyone know about the correct level in a 59 GMC 270ci?
If this was a 59 Chevy the capacity would be 5 quarts plus the filter.
Thanks in advance for your input.

 

Post a shot of the oil pan. Big trucks can hold as much as 10, pickups with stock filter hold 6 ...

 

My dad had one and would get 7 quarts for an oil change. Leave a can in the truck and after he’d use up the 7th quart it was time to think about another change. Pretty scientific, huh?

 

59 GMC 1/2 ton

 

Mine took 9 1/2 qts. With a half a quart in the air cleaner

 

Mine takes 11 1/2 qts. Oddly, the crank dips below the oil level, so I will try to run it with 8 to 9 qts.

 

The oil pump pick ups are floating and sits very low in every GMC I’ve had. The last pickup truck engines were 7 qt and looks like the red one. I ran the biggest 11-12 qt on my first racing engines with only 7 qt in them and never hurt anything.
I’ve checked the 2 I can get too and the deepest at the sump is 8-3/4” and flatter one is 7-1/4”. There are at least 4 pans I know of maybe more with military engines.
This one is a 228-248 pickup truck pan and we put 6 qt’s in the pan and 1 for the full flow added filter. I did a water check when ***embling this engine for his 40 Chevrolet and the pick up was under by 2”. I added trap doors to the existing dividers.
The best pans to cut and make custom are the larger military with the 1/8” strap stiffener on the rails.

 

Here's my pan with extra baffles, trap doors, and windage tray. 11 1/2 quarts came to the top of the original baffles. I had to drop the windage tray lower to clear the crank, so the crank would be dipping into the oil if filled to that level. The modifications work well, I filled it with water and any amount of sloshing around would not drain the area around the pump. I'm intending to fill to 8 quarts for the sump and the remote filter.

 

Nice work on the baffles. I’ve never used a a solid mounted pickup Eventho I have them.
Make sure when install the dimpled oil pump hold in on the side of the oil pump body to bring it down tight in the detent the back off a little no more than a flat on the bolt and lock it with the nut. It needs to have a slight amount of play for the distributor drive.

 

Thanks Jimmy Six! My sump is 7 1/4" deep. Whoever cut and remarked my dipstick must have gotten it right as my scribed full mark is 7 quarts with the spin on remote filter.