Oil Consumption Problem

[Malibu]

Buster, your engine is turning only around 3000 RPM at 75-80 MPH
because it has an overdrive transmission. That's relatively slow for
a 6000 rpm redlined Toyota motor such as yours and will not aggravate
oil consumption. Before overdrive transmissions were popular, Toyota
engines such as the 1975-80 20R engine (redlined at only 5500 rpm)
were turning 4000 RPM at 75 MPH and still not burning hardly any oil.

Secondly, intentionally running a Corolla engine like yours 1 quart
low on oil is going against the advice of Toyota owners manuals which
say "keep oil level near the full mark" and "if the oil level is low,
drive only at low speeds."

 

[BOBISTHEOILGUY]

Buster, there is some good points against my thoughts on the oil pressure issue, and I for one will have to stand corrected as to how this might be happening, but do stand by the point that your driving speeds may be the cause of this. As for allowing the oil to run low, well, that is a call you need to make. I know that I ran to and from texas on my 1.9L 4cyl car with that one qt low senerio and it didn't do any damage as it has not caused any oil consumption and wear numbers according to the oil analysis showed not to be a problem at that time or after. It did show my oil to have thicken up from a 40 to a 50w which was to be expected due to the 1 qt low. BTW, the ford too has an overdrive.

I'll have to re think my theory as to how the oil is getting by due to higher rpm/oil pressure. Could it be due to volitiaty? maybe and really can't rule that out as a possiblity, but most of my driving was in eve's and night time so heat wasn't the greatest factor on that run.

Thanks guys for staightening me out on my mis understanding about the rings although I do believe theres more to the higher pressure issue than just the rings.

Buster, what type of oil filter were you using and how many miles on the oil/filter?

 

[buster]

Thanks everyone for the responses. It sounds like the 10w-40 is the way to go. 1/2qt. every 1,500 miles or so isn't really that bad. My manual states that oil consumption is normal, of course a reasonable amount that is. This is my second run with s2000 and I have been using Amsoil oil filters. I stated awhile back the oil was dark at around 2k and now it is lighter. I'm assuming the oil was cleaning up and maybe the filter retained the dirt. I don't think it is the oil as much as the engine. With the mileage I have, 40wt. sounds like it is the way to go, especially in the summer. I'd try the M1 0w-40 but it seems to be thinning out to a 30wt, so Ams it is. I currently have 6K miles on the oil and filter. Oil still looks fairly light color. I'm thinking of taking it too 12K and having it checked but if I keep adding this much, it will skew the results.

[ January 24, 2003, 05:30 PM: Message edited by: buster ]

 

[buster]

Forgot to mention....does Amsoil plan on bringing out a 0w-40? I'm with dragboat, that would be nice.

 

[widman]

Before you blame the oil, if you have a pcv valve, change it. 25,000 km ago I changed it on my mazda pickup that was consuming 1 lt every 4000km or so and now I never add between 6,000 km changes. (has 160,000+ on it).

 

[buster]

I did replace the PCV valve. I'm not blaming the oil. The oil is great, it's more of the engine being older now. I going to use the 10w-40 blend this summer.

 

[huxley7]

I wish a burned oil at that rate I have a 1991 dodge monaco 500 mile to the quart next time I might buy a toyota.

 

[cryptokid]

bob, the only problem with your scenario is that the piston rings of any engine do not see any oil pressure.
they are lubricated by crankcase vapor, oil splashing off the rods/mains, or oil squirters. but they NEVER see actual oil pressure.

 

[buster]

Consumption is down alot using 10w-30. It's Mobil's VI's that cause this problem, not the wt. of the oil IMO. Low 30wt or not, it really doesn't matter. I think Mobil's VI's are more volatile and burn off easier. I have no data or scientific evidence to back me up, so it's only a good guess.

 

[mkosem]

quote:

---

Originally posted by buster:
Forgot to mention....does Amsoil plan on bringing out a 0w-40? I'm with dragboat, that would be nice.

---

They already have one:
http://www.amsoil.com/products/aff.html

--Matt

 

[TooSlick]

Matt,

You can run the Amsoil 0w-40 in gas engine passenger cars, but it's not one of their very long drain formulations. Recommended drain interval is 7500 miles or six months,whichever comes first.

I ran this formulation in my Audi 100 two winters ago, but I did not test it. I may put some in my Audi TT turbo, since that will be a more demanding application. I'd expect the additive chemistry to look similiar to the Mobil 1, 0w-40, but with a significantly higher level of ZDDP. If you send these two oils off to the same lab, I'd expect the TBN's to be pretty close. The Amsoil 0w-40 is also recommended for use in four stroke motorcycles, so I'd expect it to be pretty shear stable.

TooSlick