Oil...Where can it go?

[dude1116]

Hey All!

So I'm starting this thread because...well...the search function was frustrating me today.

I'm losing about 1.5q of oil every 2k miles or so. Question is...where on earth is it going?

I'm fully aware of the possibility of the oil burning...but I want to make sure I covered all of my other bases before coming to that conclusion.

I've changed both valve cover gaskets and do not get a burning smell. I've checked the coolant and it stays level and looks fairly clean (I siphoned some out into a bottle and looked through...is there any other way to check this?). I've looked underneath the Jeep and can't seem to find leaks (rear main seal, oil pan, oil plug, oil filter). Am I missing something? Or am I burning this oil?

Next question would be...if I'm burning it, what did I do wrong? Do I push the Jeep too hard? I always let it warm up fully before pounding in the throttle. I changed my oil every 3-5k (mostly towards the earlier end of that spectrum) and my valves look as clean as a brand new engine's. I just can't figure out what I did to cause this burning. :blah:

Any help/advice would be greatly appreciated.

 

[uss2defiant]

I'm on the same boat. I loose about 1.5-2 quarts every 3k OCI.
Can't find any problems either.
Changing the PCV helped for a bit.

What oil do you use?

I'll be trying a crankcase flush at the next OCI and trying the full synthetic route.

 

[dude1116]

I JUST switched to full synthetic 5w-30 (Mobil 1 Extended Performance) to see if that would help any and it hasn't. Prior I had been using Valvoline or Pensoil conventional in the same weight.

 

[uss2defiant]

darn....
I'm hoping that switching oil like you did would help.

Have you tried changing your PCV?

Unfortunately, I've resorted to using oil additives like Lucas or STP to slow the loss down.

 

[70AnvKK]

If you're not leaking oil out of the valve covers or rear main etc, the only other possibility is burning it. Depending on how high your milage is, that may not be totally out of line for usage. High milage engines will have wear on the rings which will result in using more oil.

If you have a large Cat dealer in your area, most of them will do oil analysis for about $40 which will tell you a lot about your engine. They will give you a small bottle to put some oil in at your regular OCI. If you do have any leaks, synthetic oil will simply find or create leaks in higher milage engines.

 

[LibertyTC]

If you have covered the leak department and no oil leaks present, then there are two sources of oil burning. One from valve stem seals, the other, rings.
The PCV should be replaced and if it is really oily/gunk, stem seals are the general cause, oh and the PCV hoses should be checked for blockage/cleanliness.
Spark plug condition can show oily residue if it's rings etc.
A compression test & leak down test will reveal much in the end on how the engine is.
The cats will burn off much of the blue, but if you start and you see any blue coming out of the pipe, you know it's burning it.

 

[libertybob]

Oil Consumption

Worked all my career in the automobile industry. Back in the 80's and 90's car manufacturers' warranty on oil consumption on new cars did not kick in until the engine burned more than 1 quart per 600 miles. The tolerance stack up (cylinder bore high side of tolerance, rings low side, valve stem bore high side, valve stems low side, etc) could allow high oil consumption. Of course the mathematical probability of getting an engine with this condition was almost 0, but it did happen. The manufacturers usually replaced the engine under good will. Imagine a customer who traded for a new car to find the new one used more oil than their old one. So, when one of my older cars consume oil, I remember this and just check the oil often. Do manufacturers still recommend checking oil level at each fuel fill up? They used to recommend this but of course few people did. Hopefully with improved quality systems the 1 quart/600 mile oil consumption standard has been improved.

 

[dude1116]

I actually had to change the PCV valve when I did the passenger side Valve Cover gasket. I changed it with a unit from Advanced Auto (In January or so?). I'll go ahead and check the lines. I just did my plugs about a month ago and none were oily. Couldn't hurt to replace the PCV again I suppose. Other than that I guess I'll just refill every 1500 miles or so :shrug:

 

[mx3_ryder]

I actually had to change the PCV valve when I did the passenger side Valve Cover gasket. I changed it with a unit from Advanced Auto (In January or so?). I'll go ahead and check the lines. I just did my plugs about a month ago and none were oily. Couldn't hurt to replace the PCV again I suppose. Other than that I guess I'll just refill every 1500 miles or so :shrug:

What is your current mileage?

 

[uss2defiant]

How was the compression test?

 

[dude1116]

Mileage is 140k. Compression can't be checked for another 2 weeks. Unfortunately I'm taking her on a 2,500 mile journey this coming week. Crossing my fingers for no problems.

 

[uss2defiant]

Bring oil with ya! I'm sure you already have them in your jeep.
I have a quart of oil, ATF+4, and DI water in mine.

 

[CactusJacked]

I JUST switched to full synthetic 5w-30 (Mobil 1 Extended Performance) to see if that would help any and it hasn't. Prior I had been using Valvoline or Pensoil conventional in the same weight.

I wouldn't have expected a drop either. As stated earlier, if you're not leaking the oil, you're burning it. Next oil change, step up the viscosity to a 10w30, and get the stuff that's designated "high mileage". Both of those things may help reduce oil consumption. One quart every 3k miles is considered in the "normal" range. You're a bit more than that, but not what I would consider terrible or threatening.....yet. It is saying your engine has a bit of wear though.

 

[Hockeygoon]

Going from 5W30 to 10W30 will not help. Going to 5W40 or 10W40 might.

 

[CactusJacked]

Depends on when and where the oil consumption is happening. 5w and 10w is the cold viscosity of the oil. 5 flows more freely than 10 does. The 30 or 40 is the oiling capabilites, what would be equivalent to using a straight grade oil, at 210 degrees. But yes, all around he may likely be better to jump to a 10w40. I wouldn't use that in the winter, but definitely would in the hot summer.

 

[dude1116]

Depends on when and where the oil consumption is happening. 5w and 10w is the cold viscosity of the oil. 5 flows more freely than 10 does. The 30 or 40 is the oiling capabilites, what would be equivalent to using a straight grade oil, at 210 degrees. But yes, all around he may likely be better to jump to a 10w40. I wouldn't use that in the winter, but definitely would in the hot summer.

I'll give that a try. Thank you!!

I was hoping someone was gonna suggest some anti-fairy dust for the oil-fairies that came to steal my oil. :favorites68:

 

[twowings]

Throw some Marvel Mystery Oil in there before the trip...

 

[CactusJacked]

I'll give that a try. Thank you!!

I was hoping someone was gonna suggest some anti-fairy dust for the oil-fairies that came to steal my oil. :favorites68:

Not a fairy, but she can fly.
My mother in law rides one of those too, but doesn't look nearly as good as that. lol...

You must be registered for see images