Oil Leak where?

[icefishingnut77]

I have a 2003 impala with a 3.4 engine in it. it has 80,000 miles on it and have had it since it was new. I have always used valvoline 5w-30 oil in it. changed every 3000 miles. when it hit 70,000 miles i changed to valvoline max life synthetic blend oil. the last time i went to change oil it was really low to the point that the check oil light came on. at that time i changed oil and today at around 1,700 miles I checked it and it is aboult a quart and a half low. I dont have any oil spots in the garage and the exhaust does not look black. where would this oil be going? Is it because of the new oil? any ansewers would be greatly appreciated

thanks
gs

[Iflylow]

I've heard that the synthetics can clean out the sludge that was sealing your oil leaks, thereby causing leaks where you didn't have any before..try switching back to the 5W-30 maybe.
It could be slowly dripping on the exhaust and burning off.
Check your radiator fluid...maybe it's leaking into it.

[Iflylow]

I've heard that the synthetics can clean out the sludge that was sealing your oil leaks, thereby causing leaks where you didn't have any before..try switching back to the 5W-30 maybe.
It could be slowly dripping on the exhaust and burning off.
Check your radiator fluid...maybe it's leaking into it.

[57chevyragtop]

You didn't say as to whether or not you do your own oil change or have it done? It's not a good idea to wait so long before checking oil levels, every fill up is best Just in case something does give way, you'll catch it early. Could be several reasons for the low level, none of which have anything to do with the type of oil. May not have been filled at the change to the proper level, service tech interupted etc. Only added 4 qts with new filter....head gasket leaking to water jacket, oil in coolant. Oil ring wear or valve guides worn, which I doubt at the mileage you stated. Leaking lower manifold gasket but would most likely see oil spots where parked with that amount of oil (loss?). I would suggest you refill and check often for the next couple of weeks....see if loss it continues.

[icefishingnut77]

yes I do it myself. I do only put 4 qts in with a filter which I Change at every oil change. thats what the book says to put in. I guess I should check it at every gas fill up. I jsut get lazy and you woulnt think you would have problems on a newer car. but it is getting older so I will check it the next fill ups. thannks for the advice.

gs

[57chevyragtop]

Here is how I do mine, I always change the filter with the oil, I prime the filter about 3/4 of the way and screw it on after putting a bit of oil on the seal. Then I add four qts...run the engine for a few minutes then shut off wait a couple minutes then check the dip stick and generally have to add a pint more or so, totals about 4.5 or 4.7 qts this way...so you might be filling it short some. Thank-you for reposting and if oil loss continues repost using this thread if not too long a time.

Best of luck on this issue...

[SpinnerCee]

I'll agree that I've seen this issue as well (2001 Impala LS, 3.8L), and for the life of me I can't imagine where the oil is going (the engine can consume as muich as a quart per month) -- there are no external leaks and it does not "appear" that the oil is being burned (it does not smoke through the exhaust) -- the "Low Oil Level" indication will come on when the engine is about two quarts low.

Maybe the oil is burning in the combustion chamber and not smoking because of the CAT and the way the exhaust system is designed? I've changed from Synthetic to dinosaur oil to test since Synthetics do not smoke as much as conventional oil, but did not notice any difference in the consumption nor the exhaust "tint" or smell. You'd have to tear down the engine and inspect the combustion chamber, cylinders, and heads to really diagnose the path oil is taking to get into the chamber -- A quick check would be to pull a few spark plugs (actually you should pull 'em all), and inspect them for thick black deposits -- since they are actually "in" the combustion chamber, they often reflect the chamber condition.

A long shot, but maybe the oil is just puddling and accumulating inside the crankcase or heads somewhere and not finding it's way back into the pan (at least to the extent that it can be measured on the dipstick)? Yeah, I know, it's really too much oil to just be hiding somewhere inside the engine, but I really don't have any other clue -- LOL.

* One more wild guess is that the consumption appears to be the greatest subsequent to an oil change and (very) slowly tapers off -- this indicates that possibly draining the crankcase allows air to enter the crankcase and oil galleys and it can take some driving for the engine to really "fill" properly?

[richtazz]

Even though nothing is coming out on the ground, look under the throttle body on the drivers side. There is a oil pump drive shaft there (it's essentially a distributor with the top cut off. Look for evidence of fresh oil on the top of the motor and transmission housing. If present, there is an o-ring seal at the top of this shaft that will start to leak oil. It will get worse and worse until it starts getting on the ground as well. Very common issue on al GM 60 degree V-6's. If it is leaking, it will require the removal of the throttle body to change the seal, as that shaft goes down into the engine about 5-6", and it has to be removed to change the o-ring.

[57chevyragtop]

That is interesting richtazz, I was not aware this was still an issue. I had that problem with my 92 Lumina.

[Lug-nuts]

I had a 3.8 that started using oil at 63K went nuts to find the problem. I found that the intake manifold had a internal vacuum leak that was causing my oil to disappear at different rates, sometimes 1 QT in a matter of a 5 day span and the it might go 2 weeks with only 1/2 QT. The new gasket did the trick in my case.

[icefishingnut77]

Ok

I have been monitoring my oil level for about a month now. It still goes down sometimes fast sometimes slow. today I went out and opened up my coolant cap on the radiator and there is some brown sludge floating around in there the car is cold and i live in minnesota. so is this sludge from the antifreeze or is the oil leaking into my antifreeze? My oil dipstick is clean oil wouldnt that be full of antifreeze if it were leaking internally? if this is oil in the radiator what happend and what do I have to do to fix it? the car doesnt overheat so ist not like the rakiator is plugged up.

thankss
garys

[57chevyragtop]

Time for a complete flush and fill radiator service...this is the result of dextron fluid used these days...should be done every 2 years from my understanding of techs I've talked with. Has nothing to do with oil leak and does not necessarily mean it's going to over heat right away. You can use the normal green fluid after a complete flush if you want as they will NOT mix. I do not do so myself, I really don't like the idea, if I would decide to sell mine, more factory correct the better in my opinion only.....Others, I am sure will disagree. As far as the oil loss, I am a bit stumped...valve guides may be worn or rings and be burning off...or leaking somewhere.

[icefishingnut77]

so ragtop you dont think that it is the oil leaking into the antifreeze? how can I tell if it is antifreeze sludge or oil in the antifreeze without bringing it in. even though sounds like i better get a flush anyway?

[j cAT]

Originally Posted by icefishingnut77

so ragtop you dont think that it is the oil leaking into the antifreeze? how can I tell if it is antifreeze sludge or oil in the antifreeze without bringing it in. even though sounds like i better get a flush anyway?

oil loss! PCV,PCV,PCV this must be replaced often or it will suck too much or get plugged up. because you change you oil often it must be sucking too much cankcase oil into the intake manifold..............

if coolant has particles floating in it replace coolant , use distilled water, replace with the SAME coolant that is in there now. make sure you put in the proper amount , as many put too much water into the mix....

[Headnsouth]

Synthetic oil will not remove sludge from your engine. if thats the problem (sludge) try auto-rx. This stuff is the cats a**.

Switching to synthetic oil later on can cause the engine to burn more oil. It did on my Saturn.