My 1998 Corolla 4-spd. auto. 120hp is loosing 3 quarts of RP-HPS 5W-30 Full Synthetic oil every 3K miles or every time i high rev., out the tailpipe as white smoke. I bought it used @95K miles. Mine didn't come w/ the manual so i was clueless for the most part. When i first got it, i switched to API Royal Purple a Full Synthetic oil brand, changing every 3000 until after the recommended 2 short intervals to prep for the long. Hoping i could i go to its oil life of 12,000; i reached 7500 miles w/ API Royal Purple & RP filter & aggressive driving after noticing oil light come on&off, esp. when i high rev. So i took it to a trusted Brake Masters mechanic and he told me that it has no oil and that it needs an oil change. So i had an oil change and They put in MaxLife semi-synthetic. I went 3000. No problem. Then on my next oil change, w/ a new certified local biz mechanic, i had him put in the jug of MaxLife Full Synthetic w/ Purolator Syn oil filter i bought rated for 10,000 miles. I told him to put in 4.1 quarts because i didn't know at the time that it takes only 3.9 quarts according to the manufacturer. So i took home the leftover quart of oil. At about 1500 miles i start having low oil problem again. So i added half a quart of the leftover oil from the jug. 1500 miles later, problem comes back again. i added a quart of oil: the rest of the jug plus leftover half a quart of API RP. A week later i had to another quart of oil! This time i added high grade RP HPS, not API certified but exceeds the SJ recommended on the cap. This oil i had bought in advance from Amazon in 6-pack. It it designed to go even longer to 15,000 miles. This time i could drive further but i took it to a recommended mechanic. He said, "the leak is internal and burns it, coming out the tailpipe as white smoke. Those engines are known for oil burn-off problems." and said not to put in synthetic because they have smaller molecules than conventional thus will leak easier. The part i thought he was tricking me was when he said to use SAE30 oil. Pepboys said that'll harm the fuel pump and that the manufacturer recommends 10W30 when above freezing otherwise 5W30. I still have another 5 quarts of this stuff so im gonna keep adding until i use it up or reach 5000 miles. An Autozone employee i just met says his wife has the same exact car in same dark-red color but in 3-spd. They've gone 100K miles w/ theirs and are at 200K miles but he recommends Castrol High Mileage 5W30 changed every 3000 w/ no aggressive/high revving. He also referred me to check online. I drive in high desert climate elevation 2400 ft. Temps in winter can drop barely below freezing and summer temps can reach 116 degrees Fahrenheit. 20% humidity avg. Temp fluctuation is 30-35 degrees bet. night & day typically. Gets hilly when going near mountains. I do mix hwy/city/stop-light driving. Usually clear skies. I usually drive daytime cause my window tint is extra dark. I've recently been averaging 29mpg. Previously averaged 24-25, lowest i ever got was 23mpg. I always fill-up w/ Top Tier gas, usually QT but sometimes Chevron. I also threw in an OEM K&N air filter after experiencing a haboob last October. I still need to get the missing battery tie-rod and get a new proper size battery from Autozone. I didn't know till recently that synthetic oil is for mechanically sound engines.
funrunner - I've been meaning to respond to your post, but with the brutally cold temperatures this winter, I've been very busy with my AMSOIL synthetic lubricants business and I haven't been able to respond. Even now it's 1:30 at night. Sorry.
First of all, much of the advice you've been given by discount auto parts store clerks and ignorant mechanics is simply flat out
wrong. :thumbdown:
I've been in the synthetic oil and vehicle maintenance/repair industry for over 30 years so the advice I am giving you is something you can take to the bank.
When an engine is burning a lot of oil, (
if it is burning it, instead of an oil leak), it shows up as blue exhaust fumes, not white. White exhaust fumes typically come from antifreeze/water and can indicate a blown cylinder head gasket, which can cause increased oil consumption as well. Also, a Toyota Corolla that is almost 16 years old, (as your 1998 is), is very likely to have an oil leak somewhere, if not more than one.
Synthetic oils are very detergent and clean out an engine that has accumulated sludge from cheap petroleum oils. This is desirable, however sometimes with an engine that has had a steady diet of the cheap petroleum oil and as a result has a lot of sludge inside, the synthetic oil cleaning the engine of that sludge can plug up the oil filter with it. The oil filter bypass valve opens so at least oil is flowing throughout the engine, but it is unfiltered oil with sludge particles in it. That unfiltered oil with sludge particles in it then splashes onto the cylinder walls where the sludge particles interfere with proper piston ring sealing/oil control, allowing the oil to go past the rings and up into the combustion chamber where it is burned and sent out into the exhaust. When the oil is then changed and a new oil filter installed, the problem is then solved as the dirty oil has been removed and a new oil filter installed. This is exactly as you experienced when you had the oil changed to a semi-synthetic, which can have as little as 1% synthetic oil in it and still legally be called a semi-synthetic oil. If the bottle doesn't tell you the percentage of the synthetic oil in the blend, (I've never seen one that does), buyer beware as you are purchasing something without knowing what you are really getting.
Then on your next oil change you switched to a synthetic oil again and experienced oil consumption problems yet again, which sounds like the synthetic oil was continuing cleaning the engine of sludge and going through the same issue again with dirty oil interfering with piston ring sealing/oil control and oil consumption. By the way, the vast majority of oils on the market, especially those found in discount auto parts stores, are not recommended for the rigors of extended drain service as they are not formulated for it. The oil companies that manufacture them
do not recommend extended drain service with their oils and they will not cover engine damage caused by using a standard drain interval oil in extended drain service. :no:
The RP oil you mentioned is not formulated for 15,000 mile oil change intervals. Per their website,
none of their oils are.
AMSOIL synthetic motor oils are The First in Synthetics, (TM), and coined the phrase extended drain interval and I offer AMSOIL synthetic motor oils that are good for up to 25,000 miles/one year, whichever comes first. :thumbsup:
"and said not to put in synthetic because they have smaller molecules than conventional thus will leak easier. " :icon_rolleyes:
The above is absolutely false. :thumbdown: High quality, Group IV PAO based synthetic oils have molecules that are all the same size, which resists high temperature burn off/evaporation or low temperature congealing
far better than petroleum oils do. Petroleum oils come from the ground and are a hodgepodge of molecule sizes, with some being
very small, others large and everywhere in-between. The smaller molecules burn off/evaporate first, leaving behind an ever thickening goo that doesn't flow, lubricate or provide the fuel economy it was originally intended to.:icon_eek:
An SAE30 motor oil is a straight grade viscosity, which means it doesn't perform very well in the cold, like a multi-viscosity oil will. Toyota engineers recommend using the multi-viscosity 5W-30 motor oil in your 1998 Corolla. When the engine is cold, the 5W flows well inside the engine, quickly reaching engine parts that need lubricating and when the engine is hot, it is an SAE 30 motor oil, preventing metal-to-metal wear.
The 3,000 mile drain pain went out with the 1960's.:thumbsup: Even the greedy big oil industry companies don't recommend such archaic drain intervals anymore as it's unnecessary. They are all up to 5,000 miles + now.
As for the oil wetted cotton gauze air filters, hold the air filter up to a strong light and note the unobstructed beams of light you can see right through the filtration media. If you can see unobstructed beams of light, how much engine wearing air ingested dirt is getting inside the engine too? If you're worried about dust getting into the engine, I personally don't think this type of air filter is one that should be considered. Oil wetted cotton gauze air filters can also cause the very expensive MAF, or Mass Air Flow sensor to go bad, as the MAF sensor is in the intake air stream and the oil from the air filter can get on the sensor and damage it.:blink:
There are many potential causes of oil consumption and one of the most common is a PCV valve that is plugged, or gummed up from the use of petroleum oils. When the PCV valve becomes plugged up, it causes the crankcase in the engine to become pressurized and this can cause oil burning. To check the PCV valve, remove it and shake it, listening for a clear sounding and distinct rattling noise. If you hear that, it means the PCV valve is functioning properly. If on the other hand it sounds like just a dull thudding as you shake it, or worse, you hear nothing at all, it means it's plugged up and needs replacing. Fortunately, a PCV valve for your Corolla is only $3.99 at Advance Auto Parts.
How many miles are on your Corolla? If that's the original 1998 PCV valve,

the likelihood of it being plugged or sticking is high.
I hope this has been of help.