Oil change help 2008 chevy

Hi so i have a 2008 chevy silverado 2500 gas and we just changed the oil and we changed it from conventional to synthetic and i put in 1 qt of lucas oil stabilizer and then 4 qts of synthetic oil and i did the oil change on my driveway that is a hill after putting in the oil and finishing the oil change we checked thw dipstick and it marked full but we took it for a drive and stopped at a gas station to check it again and the dipstick is marking half full i do this to all my vehicles this has never happened to me but first time ive changed it on a hill usually my truck only takes 5qts of oil so can anyone explain to me were the oil could have gone? and I DO NOT HAVE A LEAK! I know the hill could have had the oil go to one side of the motor and it seamed like it was full but idk if i should add more oil or not and it is on a level area now

I think the 6.0 gas V8 takes 6 quarts. You said you put in 4 quarts synthetic, 1 quart Lucas.

Either way, park it on a level surface, and check the oil first thing in the am. If it’s low, top it off.

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Unless you prefilled it, the oil went into the new filter.

According to your owners manual, what is the crankcase capacity?

As long as you are above the add mark you should be fine, checking it on a hill will throw off the reading. Park it level and check it before starting up and go by that reading.

The oil level is checked when the vehicle is on a level surface.

And on some vehicles, you wait 15 minutes before checking the oil level.


Yea i pretty much put 5 qts and at the gas station i added another half but its still marking a lil above half full thank you im sure everything is okay i was just wondering if changing it to synthetic could have had somthing to do with it

Nah, synthetic or not shouldn’t matter. The dang Lucas stuff is pretty thick, though. It might take the Lucas oil a while after you shut the engine down to drain back into the oil pan. Should be able to check it in the am (on level ground) before starting it up and get an accurate reading on the dipstick.

But if it’s a 6.0, pretty sure it’s 6 quarts.

Unlikely. I’ve gotten confused when changing my truck’s oil on a hill before. I’ve also gotten confused how much oil I’ve actually added sometimes. And other times I forget how much oil the truck takes. I expect something like that is what’s happening. In any event about the only thing you can do at this point is to make sure there’s no oil leaking out either at the drain plug or the oil filter, and otherwise just top it off as required, per the dipstick, checking after it has been parked an hour or longer on level ground. When you say it is “half full”, do you mean the oil level is between the add and full mark on the dipstick? If so, that usually means it is only down 1/2 quart.

Is there a particular reason you put in the Lucas product? Usually the recommendation here is to only use a product like that if there’s a reason. You used an oil spec compatible for the engine right? 5w-30?

Okay yea thats what my brother said that it might be cuz that lucas oil stuff is so thick it takes a long time to drain thank you

Lucas’s claim to fame is that the stuff kind of clings to stuff. Judging by their display with the little plastic gears it does (surely I’m not the only one who’s played with it at the parts counter :laughing:). If it’s mixed with 4 1/2 quarts oil, the Lucas is diluted some. But, it might take a few more minutes for the oil to drain back. Thicker oil.

I’d skip the Lucas next time, personally.

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I use Lucas in my 64 Plymouth simply because it needs a thicker oil. And I have to wonder if that stuff saved an engine at the strip one time.

I used the Lucas trans stuff in a 98 Dodge truck once. I have to wonder if it didn’t help burn up the trans haha. Probably not, but I never used it again.

I don’t understand putting in the right viscosity synthetic and then putting in something that thickens it.


Lol you have to wonder how much of the junk on the shelves really work as claimed. The only thing I have ever used that I am sure had any results is seafoam.

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Well if you go by the bottle it makes you think you are doing a good thing by protecting your engine. Easy lure for most people.

Some folks swear by it (Lucas). I dunno. It might be good stuff. I figure Wal Mart synthetic (Sooopertech!) is good enough for me.

Lucas reminds me too much of gear oil. Maybe because of their little display thing they used to have on the counter at Napa lol.

I want one of those display things now that I’ve talked about it so much. Be nice to put in my shop. Just drink beer and turn those little plastic gears.

Add oil and if it doesn’t loose anymore, you are probably fine. Do not be surprised if the synthetic doesn’t turn dirty fast as it will dissolve deposits in a 10 year old engine. I would change at 3000 miles the first time around because of this. It may get black pretty quick and this is nothing to be worried about.

Lucas is snake oil so skip it next time. I would use conventional without this rather than spend money on synthetic and use it.


How many total quarts of oil have you added? What do you mean by “half full “?

On all vehicles I regularly service, I write in paint marker somewhere inconspicuous the amount of oil, filter #, and drain plug wrench size. (I use jackstands). But always check afterwards anyways.

If this product were needed to protect your engine, the manufacturer would have told you to use it. They didn’t.

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