Engine oil capacity

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1950fordwoodie

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Gold Canyon, AZ
First Name
Bart
Truck Year
1979
Truck Model
C1500
Engine Size
406
Hey group, need an answer to a stupid question. My son and I built a small block 400 for my 79 GMC C1500, had our machine shop run and pull it on their dyno. I just dumped the break in oil and refilled it with 5 quarts. I filled the new oil filter, just shy of a quart to get it full, then put the remaining 4+ quarts in the engine. Started it up, built pressure, checked for leaks etc. After sitting level for 15 minutes, I pulled the dipstick to see if it needs any additional to top it off and was surprised to see the dipstick showing over full by about an inch. (Probably around a quart.) I'm running the factory pan that was on the 400 when we pulled it from a 79 GMC K1500. I did have to rotate the factory upper dipstick tube forward 90 degrees to clear my headers, but I wouldn't see how that would make a noticeable difference on oil level. Been a while since I've owned a small block, but back in the day, around 5 quarts was pretty standard capacity for most of them that I remember. Anyway, does anyone have an engine oil capacity chart for 1979 1/2 ton models? I'm having no luck finding a reliable answer online so far. Just want to confirm how much it should hold so I can re-mark my dipstick. Thanks!
 

HotWheelsBurban

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Hey group, need an answer to a stupid question. My son and I built a small block 400 for my 79 GMC C1500, had our machine shop run and pull it on their dyno. I just dumped the break in oil and refilled it with 5 quarts. I filled the new oil filter, just shy of a quart to get it full, then put the remaining 4+ quarts in the engine. Started it up, built pressure, checked for leaks etc. After sitting level for 15 minutes, I pulled the dipstick to see if it needs any additional to top it off and was surprised to see the dipstick showing over full by about an inch. (Probably around a quart.) I'm running the factory pan that was on the 400 when we pulled it from a 79 GMC K1500. I did have to rotate the factory upper dipstick tube forward 90 degrees to clear my headers, but I wouldn't see how that would make a noticeable difference on oil level. Been a while since I've owned a small block, but back in the day, around 5 quarts was pretty standard capacity for most of them that I remember. Anyway, does anyone have an engine oil capacity chart for 1979 1/2 ton models? I'm having no luck finding a reliable answer online so far. Just want to confirm how much it should hold so I can re-mark my dipstick. Thanks!
I think I read on here recently that there are 4 quart and 5 quart oil pans for small blocks in trucks?
Every 350 I've ever changed the oil in, held 5 quarts. Sometimes when I put 5 in though, I've gotten the results you got(even on two trucks I know have factory oil coolers because they have the HD towing package). And part of that 5 quarts, about 2/3 of a quart, is in the new oil filter when I install it, so there's clean fresh oil going into the pump.
 

ButchM

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Butch
Truck Year
1986
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K30
Engine Size
454
Bart
Some history from someone who remembers many of these changes:
-Oil pans up to 73 had a thin seal between the timing chain cover and oil pan. Starting in 74 they went to a thicker seal and the change was made to the oil pan.
-Small blocks originally had driver side dipsticks. Starting in 1980 they moved to the passenger side except for the 400. 1980 was the last year for the 400 so my guess is they didn't want to retool for a one year only engine.
GM used the same oil pan on small block trucks and many cars from 74-79, part number 465221. Corvettes were different as were V8 Monza's, some Z-28's that had windage trays etc. But many cars/trucks used that same pan with the same oil capacity. You can find 4-6 quarts if you search the interweb. I believe 5 quarts is a good number. If you have an oil cooler it will add a bit depending on the size of the circuit. As an example, I have an 86 K30 that is listed most places as a 6 qt oil pan, on a 454. It has an oil cooler and takes 8 qts to change the oil with filter. Had the truck since 1988, that's what it takes.
All that being said, if you put 5 qts in and it showed an inch high, I would remark or replace your dipstick. While the oil pans are often the same between applications, the dipstick tube and dipstick are often not. You may have either a mismatched dipstick/tube or both, or one from a different application. Dipstick heights were changed due to "packaging" for a body style requirements or other BS corporate reasons.
Long way around to say: if I had 5 qts with filter I would feel good and remark or replace the dipstick/tube. Looking for a matched set.
Butch
 

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