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Problems reading oil

I have a 2007 Chevrolet Trailblazer and a problem I’ve never had before with any vehicle. This vehicle holds 7 quarts of oil but the dipstick is not reading any oil. I had the same thing happen before I changed it and about 4-5 quarts came out. What would cause the dipstick to not read that any oil is in a vehicle, yet there is plenty in it? This has always been mysterious to me and I’m hoping someone can shed light on the mystery. Thank you all!

After you put in 7 quarts, does it read full? If so, it may be that the dipstick does not extend down to 3 quarts low. If it doesn’t read full after 7 quarts, compare it against another correct dipstick.

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It holds 7 quarts but only 5 came out, so it was 2 quarts low? Often dipsticks will not record any oil when it is two quarts low. My guess. Otherwise your dipstick is screwed up.

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Consider going to a Chevy dealership and see if an OEM dipstick is still available for your vehicle. It is possible at some point a substitute dipstick was placed in your engine.
After you changed the oil, refilling with seven quarts of oil, did it not
show on the dipstick? Possibly the oil is not draining back from the top end of the engine.

Then you were 3 quarts low on oil… a VERY bad thing… so the dipstick would show no oil on it because you are NOT supposed to run the engine that low on oil.

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As I recall, my Miata will only show down to a bit over 1 quart low, after that, it will not show oil. The distance from full to empty on the dipstick is 0.8 quarts, the dipstick can show maybe half again that amount to the bottom of the dipstick. You were running that engine with far too little oil in it as others have stated.

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I had an 03 TB, at 190k miles burned about a quart every 3000 miles. My readings were never off the dipstick, I think 1 quart low would have put it near the bottom of the dipstick, guessing being 1.5 quarts low would have not shown anything on the dipstick.

I’ve already checked and it is the original dipstick.

I had just got the vehicle and it never read on the dipstick and I was going to do an oil change but only had 5 quarts at the time. I put what I had in it (5 quarts) to see if that filled it up. I learned the capacity later, which was 7 quarts. It never showed on the dipstick with 5 quarts in it. I’m going to put another quart to a quart and a half in it to see if it reads, and if so, where on the dipstick it reads. Thank you.

Is this the vehicle you wanted to modify for more power ? If so then this is a case of you are trying to run before you can walk.

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You under filled the crankcase, it is 2 quarts low.

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The dipstick is marked with 2 small holes or a crosshatched area. Add until the level is betwee. The holes or on the crosshatch.

This is realy basic stuff. Seems you need a lot more study. Reading the owners manual will help. They are available as PDFs from GMs website if you don’t have one.

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Personally I think that is somewhat irrelevant. You learn things as you go with anything. It was something I overlooked because the vehicle is new to me. Am I to assume you never owned something and learned something new about it? If you didn’t want to answer the question, it’s a forum and you could have kept scrolling or moved to something else.

Well as I stated before I added 5 quarts and most stuff I’ve owned took 5 quarts. You’re right. I could use a lot more study. I know a lot about vehicles but it’s not all linear information. I guess another kicker for me is how busy I stay and sadly I didn’t take the time to stay on top of it. Oh well.

Did you check it immediately after you changed it? (like you should…) You should’ve known immediately that you didn’t put enough oil in

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I’ve always been told to run it a little before checking it and let it sit, that it gives it a more accurate reading. I’m guessing that’s not true?

You run it a little while (like a few minutes) for two reasons. The first is to check for leaks, and the second is to fill the oil filter. After that you let it sit for few minutes for the oil to drain back down from the lifters, and you can get an accurate reading.

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That’s what I thought. I checked it immediately after doing just that but honestly my first thought was that maybe the dipstick had been replaced with a different one. Other things had so it was just a curiosity. Plus without knowing the capacity was actually 7 quarts instead of 5, I thought there might have been another problem. I didn’t have 7 quarts at the time, not that it would’ve made the difference because I wouldn’t have put that in there without knowing how much it could actually hold. Not fully understanding the function of this dipstick hasn’t helped. I always thought the dipstick measured the entire content of oil, not just read the level between say 6-7 quarts. I am having to learn as I go, but at least I know now that this was user error and not some other mysterious problem. I appreciate all the people weighing in and everything I learned in the process. I will continue to learn more. Although, I wish I had a more linear way to learn, I’m sure I will fit it all together eventually. :sweat_smile: Thanks again.

Ok guys lets get a couple of things in line. 1st never do any work on any vehicle maintenance process until you have ALL THE NEEDED SUPPLIES AT HAND!!! you should never run any auto 2 quarts low it causes inadequate oil circulation which causes a lack protection to the bearings and other things.like wearing out crank bearings quickly. So always make sure you have all the things you need to do the job BEFOTPRE you start the job. 2nd ALL vehicle manufacturers require that you presoak the new oil filter by filling it with oil and letting it sit for 10 min estimated so the filter can wik up the oil. After its done wikking the oil then install. This prevents the delay of oil distribution which causes damage to the engine from running it without oil. When you dont wik the filter the engine runs for up to 5 minutes without oil circulation.the dipstick is an estimated oil level not exact. This is why there’s a 1 inch area on it that is marked. There must be oil in this 1 inch area. If there isn’t DO NOT START RUN OR DRIVE THE CAR UNTIL YOU CORRECT IT! ALWAYS refer to your owners manual for the type of oil your car requires for the season you are in and the capacity of oil needed. New cars need specific types of oil most much lighter viscosity than the older cars so NEVER ASSUME you know what you are doing because this is the main cause of new cars having the warranty voided and people ending up with a brand new car with a blown engine. The other cause of voided warranty is someone who is not a certified technician doing what they think is maintenance but its not done properly by following the maintenance checklists. Regular joe car owners cannot get hold of the checklists for this reason.the warrantee companies will not carry the warranty on a vehicle that isn’t maintained by a properly certified technician. This story is a prime example of someone who has no business being under the hood of any car messing around and doing things they have no business trying to do.

Checklist is a secret ? :astonished: Certified Technician ? If the owner has oil change receipts the vehicle warranty will still be good .

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