Oil change

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ben82k10

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Stupid question I know but hear me out. I searched before posting but everyone seems to have a different motor so that’s why I’m asking. I’m new to the square bodys. It’s an 82 k10 with the original 250 inline 6 4.1L. How much oil, weight and what type do you all recommend? This is my first oil change since I got it. I don’t know the miles because the Speedo wasn’t hooked up so I’m starting fresh on everything. The guy I bought from was the 2nd owner and only fixed it up didn’t drive it. It was an old far truck.
 
DoubleDingo

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Carb'ed Vortec 350
Yep, 5 quarts for the 250. Not sure if the filter @Terlingueno also fits a 250, but your local parts store should be able to get you the correct one.
 
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ben82k10

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Synthetic or no? Usually you switch to synthetic due to high mileage but I’m not sure what mine is.
 
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I am partial to synthetic but due to it being more slippery than conventional oil it is a good way to find leaks ... :eek:

So, if you don't know the history of the motor and it is not leaking now dino oil may be the safe route to take .


I am currently running Valvoline Restore & Protect 5W30. Full syn with piston ring cleaning action.

:waytogo: I like it so much it is in all of the vehicles we have AND the lawn mower !! :anitoof:
 
DoubleDingo

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No. Conventional. If you do use synthetic, add zinc. I just run Valvoline Conventional 10w30, but you can use the VR oil mentioned above
 
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peats

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I use 15-40 rotella per my engine builders recommendation. I also add 6oz of zink additive for all flat tappet engines.
 
Sad Sack

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When I got my square the mileage and maintenance was unknown, threw in a can of engine flush first, drained and then 4 quarts of Val Max Life 10w-30 with a Wix filter, one quart of Lucas Oil Additive and a since it had a real tiny bit of oil drippage I also added a 8 ounce bottle of ATP AT-205 and it fixed it right up, been 1 1/2 years running strong and no drips...yet.
 
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Hunter79764

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Unpopular opinion, but these days, synthetic is overrated for an older, stock engine. Run it in a race engine built for it, or in the newer daily drivers, and stretch the oil intervals out a bit. But an older truck? Stick with conventional, change it after 3k or a year, whichever is less. Wix or other good filter and decent conventional will keep costs low and keep fresh oil in it, which is much more important than any initial quality difference (avoiding all extremes, of course). Great oil isn't much better than good oil, it just stays good longer. Perfect for a Honda driving 500 miles a week, but unnecessary for a fun truck driving 1000 miles a year.
 
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Ricko1966

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Too much zddp is bad also,so add it accordingly. I wouldn't add anything to an oil that's already over 1000ppm. 60s oil was only 600ppm. I think part of the problem today is too much,too low rpm use. Look at where your cam is, it's underneath the lifter valley with a big old slab of iron over it,most of the oil for the cam is the cast off from the crank below it,there is no pressure oil for the cam lobes. Lower rpms means less oil cast off from the crank and at a lower velocity,so less oil for the cam. That's why you have to keep the rpms up on a break in to keep the cam oiled. The guys with solid rollers are having problems too,if they idle too much,or keep the rpm too low. It's not a popular opinion but it's my opinion.I think part quality is an issue too. But flat tappets used to live with 600ppm zddp but we turned them regularly at 3000 rpms.
 
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