oil consumption, still!!!!

[Drew99GT]

Well, I've posted about this before. My 94 Corolla that I recently bought burns oil like a mad man. On the highway, it's about 1 quart/1500-2000 miles I'd say, but it seems to be worse in town. I recently filled up with 5w-30 Pennzoil high mileage, and it's burnt darn near 1/2 quart in 400 miles

I've done Auto RX, didn't help consumption at all. I thought this car was well taken car of (1 owner with ALL the records), but I think the other owner was a bit lax on oil change frequency. It doesn't smoke at all. Doesn't leak or drop any. Where is the oil going? Past the rings? I guess it's on to 40 weight next to see if that improves things, but I'm limited to 5w-40 because of winter conditions. Don't want to run regular 10w-40 because of the noted thinning, and 10w-40 high mileage would be too thick for cold temps IMO. So, 5w-40 Rotella it is because of price mainly and it is a solid oil. BUT, I'm still worried about the whole diesel oil in a gas engine thing

Even if it slows consumption a bit, it will still be passing a lot of phosphorus though the cat. Also, on the Rotella.com forum, the "Tech expert" indicated that if your car calls for any of the GF standards in the manual, to not use it for fear of catalyst poisoning. He says to only use it in a gas engine if your manual only calls for an API oil designation such as SH/SL etc. What do ya'll think? Has anyone out there successfully run one of the mixed fleet oils for a LONG time in an oil consuming gas engine?

 

[ToyotaNSaturn]

Drew, Don't worry about converters on your car seizing up prematurely with the extended use of HD Delo oil. Spend a good while in the Light truck forum, many people use 15w-40 for the life of their vehicle without any cat issues. I was just as concerned as you and had posted essentially the same question. But look at the facts--will 100 or 200 ppm of phosphorus make a difference? No, unless the car is consuming the oil. If the car stops consuming oil with the thicker stuff, then it's a win-win.

I would suggest performing a run of Delo 400 or Delvac 1300 (the cheap stuff) unless weather is too cold, then your 5w-40 plan sounds like a winner. Amsoil makes a 15w-40 blend for around $4/qt. How about M1 15w-50? It will flow better in the cold than a dino 15w and will most likely take care of any consumption issues. I ran this oil last summer in my car and would run it again in a heartbeat--it's good stuff.

 

[Drew99GT]

Here is what the Tech Expert says to every person asking about Rotella in a gas engine on www.rotella.com

ROTELLA T Multigrade is a universal oil, meeting API Service Categories CI-4 for diesel engines, and SL for gasoline engines. Where the engine manufacturer recommends oil meeting either one (or both) of these Service Categories, or earlier categories, ROTELLA T can be a good choice. However, ROTELLA T does not meet all the requirements of ILSAC and API Certification Mark (starburst symbol) standards, sometimes specified for gasoline engine oils (in addition to API SL). These additional standards deal with fuel economy, and also limit phosphorus content (an element in all engine oils, but usually at a higher concentration in diesel oils). Phosphorus can affect catalyst activity in some exhaust emission control systems.
If your manual specifies only API SL (or earlier designation), then the catalyst is likely not sensitive to higher levels of phosphorus. If it also specifies ILSAC standards, using ROTELLA T may risk some catalyst activity loss.

 

[Drew99GT]

quote:

---

Originally posted by ToyotaNSaturn:
Spend a good while in the Light truck forum, many people use 15w-40 for the life of their vehicle without any cat issues.

---

That's in diesel engines though, isn't it?

 

[ToyotaNSaturn]

Yes, it's primarily for diesel engines, but there's guys who run gas engines who post there. I spent some time in there and it opened my eyes that 40w oils aren't all bad. Yes, there's an economy hit, but that goes without saying.

I ran M1 15w-50 last summer in my Saturn, with the A/C off I was getting 33MPG. I'm getting 31MPG now with 10w-30 oil. I thought my car was burning the thicker M1, but it wound up being incorrect measuring techiniques on my part.

After spending too much time in the VOA and UOA forums, there wasn't THAT much difference between car oils and Delo 400 in the Chevron flavors. Yes, the light truck ones are thicker and contain more phosphorus, but it's not THAT much more. Therein lies the rub in my mind---all for CAFE. It's got to be that way otherwise car oils wouldn't be just under 1000ppm and the Delo's of the world run about 1200ppm...just over 1000pm. Heck the new M1R has 1900ppm of phosphorus! I wouldn't want to run THAT in my car!

I don't believe the cat converter of the car would notice the difference of the phosphorus level IF it's not being burned.

Don't worry about it, you have nothing to lose by using these oils which I feel are better quality than the ones limited by the GF/3 specification.

 

[Jelly]

Yes, I've ran HDEO's in gas engines, and I've never had a major catalytic converter meltdown...have I had converters go south? Yes...but all with a good deal of mileage on them.

Will higher phosphorus levels being ran through your converter cause a shorter life span.

Sure, but you have to consider two things:

1. Given identical consumption between two oils, but one with significantly higher phosphorus levels, one converter will last 100,000 while the other one will last 120,000. Who cares though when you have an oil that is protecting your engine better...much easy to chop off an old converter and replace it than replace your engine...and much less expensive.

2. Going to a thicker oil, such as 5w-40 Rotella, will definitely reduce consumption in comparison to a 5w-30 PCEO...so, the level of oil going through the converter will be less, making the higher phosphorus levels a non-issue. Heck, the converter might even last longer with the Rotella!

Remember, even the latest HDEO's are API SL certified...

Make the switch to Rotella 5w-40 and have fun!

 

[Bobert]

I've seen quite a few people have good success at lowering consumption with Castrol Syntec 5w-50. I think a 50wt. should be fine for the Colorado climate.

 

[Drew99GT]

quote:

---

Originally posted by Bobert:
I've seen quite a few people have good success at lowering consumption with Castrol Syntec 5w-50. I think a 50wt. should be fine for the Colorado climate.

---

Except it was - 15 degrees F a few nights ago at my parents cabin!

 

[ToyotaNSaturn]

-15F ? THAT'S cold! I guess your plan to use 5w-40 Rotella is the best ticket.

+15F Thick M1 or Delo 400 will work well.

Either way, keep warm!

 

[Bobert]

The new Mobil 1 5w-40 Truck and SUV formula should be good also. The bottle even says it controls oil consumption. This might be the ideal choice. Any 5w-xx oil should be good for -15F.

 

[ToyotaNSaturn]

Bobert has some real good suggestions. I wouldn't hesitate to use the Castrol 5w-50 as it has some good UOAs recently.

Bob, are you using the M1 5w-40?

 

[Bobert]

quote:

---

Originally posted by ToyotaNSaturn:
Bob, are you using the M1 5w-40?

---

Right now I'm mixing M1 10w-30 and M1 15w-50. The M1 5w-40 T&SUV is definitely on my short list of "oils to try". Soon as I see this oil around my area I'm going to pick a few quarts up.

 

[Yuk]

quote:

---

quote:
------------------------------------------------------------------------
Originally posted by Bobert:
I've seen quite a few people have good success at lowering consumption with Castrol Syntec 5w-50. I think a 50wt. should be fine for the Colorado climate.
------------------------------------------------------------------------
Except it was - 15 degrees F a few nights ago at my parents cabin!
------------------------------------------------------------------------

---

I've used Castrol Syntec 5w-50 for over 8 years in 5 different cars: 1986 Ford Escort, 1987 Honda Civic, 1988 Nissan Sentra, 1989 Mazda MPV and a 1999 Volkswagen Passat. The '88 Sentra and MPV still use Syntec 5w-50. I've never had any cold start issues that were not battery related. The most recent 5w-50 cold start was at -42°C. A block heater was used on this 170,000 mile Mazda engine, but I don't think under these conditions I would have wanted to start any engine without a block heater, regardless of the oil used.

Based on my non-scientific experience I think Syntec 5w-50 would be a safe choice, 365 days a year in Colorado.

BTW. The coldest temperature recorded on the planet today was in northern Saskatchwan, Canada. -52.3°C, no wind chill!

 

[slalom44]

I'd like to make another suggestion to Drew. You might want to do a compression test and leak-down test on your cylinders. The compression test will tell you if your oil consumption is coming from worn rings. The leak-down test will tell you if your valves are seating properly.

Also, check your fuel economy with each gas tank. That's another indicator of compression. Also, have someone start your engine after it has sat overnight while you stand behind it and look at the exhaust pipe. Do you see a puff of blue smoke (not black) right when you start it? That would indicate you have worn rings/cyliners.

How many miles do you have on your car? I have a '95 Corolla with 1.8L & manual tranny. At 199,000 miles, she purrs like a kitten, and doesn't consume a significant amount of oil. My car has seen mostly Syntech filters and Syntech dino oil with OCIs of a little over 3000 miles. This engine was designed to last forever with reasonable OCIs.

 

[Dr. T]

Of course...a 50 weight doesn't matter what winter conditions you're in...it's the first number that matters. eg. I wouldn't use a 20W-50 in CO or anywhere below 5F.

However, a 5W you'll be fine down to -22F...even if it's a 5W-50. So whether you choose to use a 5-40 or a 5-50, it won't matter. But, a 15-40 will matter and will only suffice to about the same as a 15-50 (that being ~5F). Likewise, a 10W-40 will not perform as well as a 5W-50 either.

 

[Drew99GT]

quote:

---

Originally posted by slalom44:
I'd like to make another suggestion to Drew. You might want to do a compression test and leak-down test on your cylinders. The compression test will tell you if your oil consumption is coming from worn rings. The leak-down test will tell you if your valves are seating properly.

Also, check your fuel economy with each gas tank. That's another indicator of compression. Also, have someone start your engine after it has sat overnight while you stand behind it and look at the exhaust pipe. Do you see a puff of blue smoke (not black) right when you start it? That would indicate you have worn rings/cyliners.

How many miles do you have on your car? I have a '95 Corolla with 1.8L & manual tranny. At 199,000 miles, she purrs like a kitten, and doesn't consume a significant amount of oil. My car has seen mostly Syntech filters and Syntech dino oil with OCIs of a little over 3000 miles. This engine was designed to last forever with reasonable OCIs.

---

I've done a compresion test; speced out perfect. Didn't have a need to do a leakdown test. Valve stem seals seem to be OK; no smoke at startup or when I hit the throttle after coasting/under vacuum.

I don't get it! I'm fearful of 5w-50 for obvious reasons.

 

[Drew99GT]

Oh, mileage is only 80,000.

 

[Bob Woods]

Have you taken a really good look at your crankcase ventilation system? If your not burning it or leaking it, its got to be going somewhere.