Where did all my oil go?

[Riad]

Yeah I did a search on oil leak and learned that there could be bad main valve seal. I am using synthetic Mobile 1 with BGMOA, it's been about 1500 miles now since my last oil change. This morning the oil light came on then went off after a minute or so. Never came back again. When I got to work I checked the deep stick and looks like the oil level is really low. I have got 111K miles on it so far. Is an oil consumption problem? How do I cure it? How do I check to see if the main seal is bad? Can I replace the main seal myself or this has to be a trip to the dealer.

Thanks for the help guys...

 

[elmariachi]

Have you crawled under the truck to see if its wet? Do you have oil where you park? Its either leaking or going out the tailpipe.

 

[Riad]

Yes, I have looked under and it is wet. Is it leaking through the oil pan? Do I need to replace the seal on the pan? No black smoke and no oil/oil puddle on neither on my drive way or at work's parking lot. No oil on Diff either. Looks like the oil leaking some where from the pan and going towards the tranny pan. What would be the cure?

Thanks

 

[RavenTai]

there are several common leaks that will put oil on the oil pan, front main seal, rear main seal, and the rear pan arch. also oil filter changes will douse the left side fo the block in oil.

to figure out what to fix you need to find out what is leaking, crawl under there and clean off all of the oil with engine degreaser, solvent or soap and water. start the engine and see where the oil first shows up at.

 

[Rookie2]

there are several common leaks that will put oil on the oil pan, front main seal, rear main seal, and the rear pan arch.

Any of these are pretty good size bannana job's.

Nothing wrong with tracking the source like Raven has mention, but before you get elbows deep in doing or paying for one of these repairs, I would try a different motor oil. You're not the first one to complain about excess comsumption using Mobil 1 synthetic. You may want to back it down to something like Chevron Delo 15w-40 or Mobil Drive Clean Plus High Mileage. Some consumption/leaking is not a big deal, expecially if you're not dripping on the driveway. You can buy a lot of oil for what it will cost to fix one of these leaks.


Rookie2

 

[landtoy80]

I had major oil consumption with M1 at high rpm's, had a oil pan leak (from the front arch) and the timming cover was seeping.
I went to RotellaT 5w40 syn oil.
My oil leaks stopped leaking (I don't know how long it took) and the timming cover is not seeping.

I am not saying that RotellaT syn is the BEST OIL but it worked for me.

You may want to SeaFoam your motor, or have a shop decarbon you motor.

 

[ryanjl]

My engine burned through a bit of M1 5W-30, but is much happier with M1 OW-40.

I'd recommend just chaning oil first.

 

[maxnharry]

I had the same problem with Mobil 1. I switched to Rotella and the problem went away!

 

[Riad]

Thanks guys. I will start with a different oil first. So what is the logistic with a heavy weight oil instead of changing any of these seals? I know changing seals are more costly but does a heavier weighted oil hurt the engine, shot/long run? Does the oil consumption go up over time? Let's say I change all the seals later, can I go back to the standard oil spec?

 

[landtoy80]

The reason for the "light oil" is a USA thing. It saves gas. It makes the car makers average gas milage go up.

The rest of the world uses the REAL viscosity chart.

 

[RavenTai]

The 5/30 and 10/30 spec is EPA driven, a compromise between best for your engine and best for Corporate Average Fuel Economy (CAFE)

Look for the Australian oil chart for this engine and much heavier oils are recommended. In Aus 5w-30 is only recommended in cold weather where the temperature will not go above 50°F

R2 you have a good point, I traced my largest leak to the rear main, at ~2 qts per OCI I am not pulling the transmission. It can wait for an engine rebuild.

My consumption has actually slowed down lately, I am about 3.5K into a 5K OCI will be adding the first make up quart soon.

 

[landtoy80]

<<<<<Look for the Australian oil chart>>>>

TOOOOOOOOOOOOOO SLOWWWWWWWWWWW Raven

 

[RavenTai]

LOL yep

 

[wob]

I had little to no oil consumption / leakage problems with my 96 - 110K miles until I switched to M1 5W30. Then, it started leaking like a sieve. I went back to dino, still leaked some, not as bad, and now I'm using M1 15W40 with very little oil use again. I also ran Auto RX after the initial M1 fiasco.

 

[Riad]

Wow, I didn't know that, well that makes sense now. I wonder if switching to let's say 15W50 would effect my emission test. How many qts do you guys use in each oil change, 6 or 7.5 (with oil filter) as the FSM says? My gas mileage is good enough for me (much better than my old truck). 321 Miles a tank. Will the 15W50 do bad on the mileage?

 

[cruiserman]

I had major oil consumption with M1 at high rpm's, had a oil pan leak (from the front arch) and the timming cover was seeping.
I went to RotellaT 5w40 syn oil.
My oil leaks stopped leaking (I don't know how long it took) and the timming cover is not seeping.

I am not saying that RotellaT syn is the BEST OIL but it worked for me.

You may want to SeaFoam your motor, or have a shop decarbon you motor.

Kurt, Where are you buying the Shell oil? It would be nice to stop the timing cover seep my rig has.

 

[Rookie2]

My consumption has actually slowed down lately, I am about 3.5K into a 5K OCI will be adding the first make up quart soon.

With a small leak, your actual consumption's probably next to nothing. I don't have any leaks, and that was about my consumption rate when I was using Chevron Delo. Jury's still out on the Mobil Drive Clean plus, as I'm only about 1500 miles into it.

What motor oil are you running now... did I recall you making the synthetic switch? I'd assume you're still Dino or Blend at 5000 OCI.


Rookie2

 

[RavenTai]

With a small leak, your actual consumption's probably next to nothing. I don't have any leaks, and that was about my consumption rate when I was using Chevron Delo. Jury's still out on the Mobil Drive Clean plus, as I'm only about 1500 miles into it.

What motor oil are you running now... did I recall you making the synthetic switch? I'd assume you're still Dino or Blend at 5000 OCI.


Rookie2

Yes I think most of the loss is leaks and through PCV not past the rings or guides,

I have been running different flavors of Mobil 1 since shortly after I bought the rig with 106k on the clock, first 2 oci's with Delvac 1 (5w-40) last summer then last fall 15w-50, through the winter 10w-30/15w-50 mix, and this spring 0w-40. I am keeping the OCI's short for synthetic because I have a lead problem. if I can get that sorted out I am going to put on my bypass filter and ease up to 10k OCI's

have about 1500 miles left on the 0w-40 and I will start the first Auto-Rx cycle, have 3 bottles of Arx, 30 quarts of Wal-Mart dino oil and some non 20004's to use for the 4 cycles.

I have not been able to make any conclusions about what weight I want to run, after the Arx cycles will try the new 10w-40, probably wind up with it or the 0w-40, the 15w-50 was my best results good (though not really conclusive with only one OCI) but I think to thick for winter.

 

[tea LC]

great i just changed my oil with 5w30 M1 -- thanks all who recommend based on my "search" < see, this is why search sucks!!!

 

[tarbe]

The reason for the "light oil" is a USA thing. It saves gas. It makes the car makers average gas milage go up.

The rest of the world uses the REAL viscosity chart.

That chart is slightly retarded

5W-30 and 10W-30 oils have more or less the same viscosity at 100C (in fact, I have some 5W-30 Havoline synthetic that is thicker at operating temp than the 10W-30 Havoline synthetic).

So why would 5W-30 only be good up to 50F and the 10W-30 past 100F? Think about it....they are both quite a bit higher viscosity than ideal at start up, and the same viscosity (10 - 11.5 cSt in most cases) at operating temp.

BTW, it is less about whether the oil is 11 cSt (30 wt) or 14 cSt (40 wt) and more about the additive package and the stability of the base oil. It's not just about viscosity...not by a long shot.