The other day I changed the oil in my TrailBlazer, and I'm trying to save my waste oil for an oil burning stove. I had just emptied my drain pan, so I figured I'd have seven quarts in there, since the I6 4wd TrailBlazers have that bastard axle-through-the-oilpan deal.
I began to pour the oil I just drained into the 5 qt jug I had just emptied, and I filled it up. So I sat down my drain pan, and went about doing another task. A short while later I looked over, and realized that either I'm a magican and squeezed 7 quarts into a 5 quart jug, or I'm losing oil.
I use Mobil 1 full synthetic, and change on 5k intervals. I don't think anything is majorly wrong, oil looked good and the thing runs great, it's just a 200k mile early 2000s GM. It's going to use a little oil.
So yeah. Check your dipsticks, people!
In reply to BoostedBrandon :
Switch to non synthetic for an oil change. It may dry up. Have seen this happen on multiple high miles GMs. Doesn't hurt anything to try, at least.
This is assuming that the oil is being lost through the rings. Interestingly, between this and another observation, I wonder if heavy decarbonization treatments like Run-Rite or BG aren't "unsticking rings" but clearing the oil wash off of the cylinder walls and allowing the rings to scrape the bores glaze-free...
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HalfDork
9/14/19 4:41 p.m.
It could be like my miata, which will say it’s a quart low, then you drive, shut down, wipe dipstick, place back in, pull out, and there’s magically A LOT MORE oil on the dipstick than before.
In reply to _ :
I noticed that in Miata too. Thought I was going crazy.
In reply to Knurled. :
Hmm, never heard of this before. May try this.
I used to have a 90s Tahoe that I ran 20w-50 basic Castrol in. Once it got well over 200k it liked to consume anything thinner and didn’t seem to run right. Ended up selling it with 385k on it still running
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HalfDork
9/14/19 9:28 p.m.
CyberEric said:
In reply to _ :
I noticed that in Miata too. Thought I was going crazy.
I’ll save you some time. It’s not the pcv system. I just did mine. Didn’t affect anything. Still randomly throws oil on the dipstick.
First time it did this I thought I had overfilled it. And the weird part is you pull it out, see a ton of oil, wipe it again, put it back in, and the same results happen the second time.
You wipe your eyes in disbelief.
My GMC has always run regular Dino juice. It uses one quart every 3k. It just turned 348k last week. Most is from the seeping valve covers.
Vigo
MegaDork
9/14/19 11:35 p.m.
Well, 2 quarts low is usually just the very edge of having consequences, so you basically caught it in time!
In reply to BoostedBrandon :
If you run low on oil the timing chain pays the price. It’s oiled by splash lubrication.
NickD
PowerDork
9/16/19 8:00 a.m.
_ said:
CyberEric said:
In reply to _ :
I noticed that in Miata too. Thought I was going crazy.
I’ll save you some time. It’s not the pcv system. I just did mine. Didn’t affect anything. Still randomly throws oil on the dipstick.
First time it did this I thought I had overfilled it. And the weird part is you pull it out, see a ton of oil, wipe it again, put it back in, and the same results happen the second time.
You wipe your eyes in disbelief.
It seems like Miatas are also particularly sensitive to the car not being on level ground. I was at a dyno day once, checked the oil level in the parking lot to make sure everything was okay and there wasn't a drop on the stick. Freaked out, ran to a parts store, bought a jug of oil, come out and pull the dipstick and now it's waaaay over full. Got thinking and it was at a slight nose-down angle at the shop parking lot and now was at a slight tail-down angle at the parts store. Found someplace that seemed completely level, and now the oil level was halfway on the operating range segment.
My Expedition burns a good bit of oil. I do synthetic every 5k or so (193k now), and i'll usually add a quart or so in between oil changes
