I'm owner #2 of a 2002 LS 430 with 144,000 miles. I am confident it had impeccable service when I got it 6 years ago with about 54,000 miles. I have always changed my own oil; OEM filter and Mobil 1 5W-30 @ 5000 to 7000 mile intervals. It seems to be getting a quart low just before I change it. The reality is that I add a quart and drive another 1000 miles or so and do the change. There is never any observed smoke, including after a month-long sit and or under fully acceleration. No leaks are detectable.

A couple of observations: 1) I have never had another vehicle that is so tough to determine "full" on the dipstick. The Mobil 1 and the dipstick seem to conspire to create difficulty in seeing the legitimate level vs. tube residual oil in the tube. Sometimes it takes 5 qts., sometimes 5.5 (yes, I'm sure I have allowed a much longer drain, like overnight, on occasion, vs. "gittr done") ... so I struggle to get the baseline right, but I check the fill several times over a few days and do my best. 2) The oil is so clean at 5000 miles that it's still hard to get a precise dipstick read. But it sure seems to be right above the bottom mark (one quart low) when the Oil Level annunciatior comes on.

I'm about to change the oil, but I think the rate of disappearing oil may be increasing. I forgot to log exactly when I noticed being about a quart down, but it seems like I topped it off about 1000 miles ago and now it's almost a quart down again. Obviously I am concerned. Should I switch to conventional oil this time, and see if there is a consumption change? Based on searching this forum and my past history with Toyota and Lexus engines, it's very unusual to use oil in the low to mid 100k range. Any ideas on what might be going on?

 

Have you called a dealer? Have they said if there is any diagnostic engine test to check compression and the rings and such?

 

It would be weird to have oil consumption (via burning oil) if the oil is remains so clean over the oil change interval. I might look for some minor oil seepage (rather than a faster leak) that might not show as oil spots in the garage floor but still be slowly seeping. Get it up on a lift and have a good mechanic check it for seepage. Then run compression tests but my guess it that its likely not burning oil - if it was the oil would be more brown and contaminated with blow back and carbon from failing rings.

 

Oil blackens after maybe 500 miles of local and about 1000 miles of highway driving, so I can't see how your oil can be so "clean" at 5000-7000 miles that you can't check the oil level correctly. I know the LS is a smooth runner, but I find this strange.

As for level, 5 qts (atleast for my 2004) brings the level to the middle of the hash mark (with filter change) and 5.5 to the full mark.

For the burnoff, if you don't see any major leaking or dripping, then it's just minor blowoff through the seals for now and you probably won't see any smoke unless under the highest of revs, which for the LS is almost never as the trans. is geared to almost never go above 4-5K RPM.

 

Agreed, especially with conventional oil, but that has been pretty standard for this car with Mobil 1. My LS 400 was similar, but a bit darker at oil change time. I have a 04.5 Cummins-powered Dodge Ram that blackens the oil almost immediately due to an "extra injection event" fuel-wasting emission b.s. scheme. You would want to change the truck oil based on a visual one week after a LOF, and the LS would be a candidate for perpetual oil running based on the eyeball. But I do oil analysis on both, and the numbers support continued running beyond my changes. The 5000 to 7000 interval is a "just because" number that probably is environmentally and economically wasteful.

I guess maybe it's time for compression/leakdown testing. Gotta figure this out, but there are not many good scenarios. It looks like pull-out engines aren't available for much less than $4k, even doing all the labor myself. Given that these cars almost never need an engine, I would have thought the supply/demand formula would make the engines cheaper. WTF with the asking prices for salvage engines when there does not really seem to be many vehicles that need them? Sadly, the numbers do not crunch for dropping $4 grand-plus in a car that's might be worth $10K. My "drive it till it dies" plan was supposed to go at least another 100,000 miles! This is not the kind of excuse I wanted to rationalize a 07 LS 460!

 

I would try an oil change with dino oil and see what happens. My Lexus service manager recommends using dino oil in this engine. When I picked up my car today, I mentioned that my loaner 2010 RX350 ticked on cold starts. He said this is common on the RX350 due to relocated injectors and changing to synthetic oil.

 

I observed several items in your post. #1) you are having a difficult time obtaining an accurate baseline reading with the dipstick. Without this, your measurments/estimates are useless. #2) STOP using the dipstick as your measurement guage. I know it's there to use, but it's not 100% accurate. IT'S AN ESTIMATE! Who knows---it may be bent (preventing an accurate reading), it may be an aftermarket or replacement or WRONG dipstick and you may THINK your readings are low, etc.

I don't know what the "book" calls for capacity w/filter change on your LS, but I would put that EXACT AMOUNT THE BOOK CALLS FOR, during your next oil change. THEN...and only then...observe as best you can on the dipstick to see where it indicates!

After 5k miles, observe as best you can where the oil level is on the dipstick and then when you change the oil, POUR THE USED OIL BACK INTO THE EMPTY OIL CONTAINERS! I know it's a pain in the a$$ but it will put your mind at ease. ALSO---observe where the FULL LEVEL is on the oil containers before you pour it into the engine so you know how full to make the quart containers! I would get a permanent magic marker and mark the FULL on the quart bottles before you pour them into the engine.

I know what you get OUT of the engine won't be exactly what you pour INTO the engine, but your findings may surprise you........

This is the ONLY way to accurately guage how much oil ur LS is consuming whether burning or leaking. Using the dipstick is merely an estimate, and it might not even be the RIGHT disptick!!!!!!!!

Let us know your observations.

BTW---overfilling with oil is more harmful than being low (to a point obviously)...

 

If the car used normal oil (non-synthetic) for most of its life then that could be the reason its leaking. The actual chemical structure of synthetic is much smaller then conventional oil making it easier to leak between places normally clogged up by the conventional oil

 

I have some bad news for you. Despite all the marketing hype, I've had very bad luck with Mobile 1 10w-30 oil. I've used this oil exclusively in two previous cars. Both were burning oil by around 100k miles. I'm sure I will get flamed for even suggesting that Mobil 1 is a bad oil, but I will never use that oil again as a result of my personal experience with it. I maintained those vehicles extremely well, one was a Honda and one was a Nissan, both with highly regarded engines not known to burn oil . . .

Andrew

 

Synthetic oil was developed for aircraft engines. Aircraft engine manufacturers have the necessary equipment to analyze the oil and quantify metallic particles. They do this during the development stage of new engines and can detect abnormal wear in a new engine and start to look for the problem. This also allowed them to quantify the reduction in wear in using synthetic oil instead of mineral based oils.

Aircraft engine manufacturers wouldn't think of using mineral based oils. They know better.

 

I have put 200K miles on a few engines with Mobil 1 only.
ML320 had 212,000 when I sold her all with Mobil 1 no leaks, no burning.
My LS 400 has 190K same deal...

 

The spec for oil w/ a filter change is 5.5 qts.

Not all M1 grades are created equal. For the consumer grades, I would use the Mobil 1 0w40...this is the ACEA A3 grade recommended for Porsche/Benz/BMW/Nissan GTR while the other M1 weights are ACEA A1 for Chrysler/GM (which would you trust more?). The 0w40 has a higher viscosity, yet better flow when cold, so it should slow down your consumption. When my honda prelude was new, the engine burned 1 qt every 3K miles using dino 5w30. After changing to 0w40, oil consumption was reduced by about half. Note that the M1 grades other than the 0w40 are NOT approved for European engines. If you use the cheaper M1 grades in your Porsche and drive it hard, you run the risk of premature engine wear! I've tried M1 10w30 in my honda and toyota truck and was disappointed...dragged my fuel economy down by 5-10% in both cars when averaged over 5000 miles. The only other grade of M1 I use is the Mobil 1 Delvac 5w40 engine oil and M1 Delvac 75w90 GL-5 gear oil. The M1 Delvac 5w40 is for diesel and gasoline engines, so it contains more detergents to clean any varnish you might have in your engine from running years of dino. When I buy any used car with > 30K mi, I generally run 10K mi on the M1 delvac 5w40 to clean the internals of the engine of varnish, then switch to 0w40. The M1 delvac is only available at commercial fuel supply shops and truck stops and is pricey...smallest size is 1 ga (4 gal per case); a case usually runs $125 ($7.80/qt) while the M1 0w40 was running $39/case of 6 qts ($6.50/qt) at my local commercial fuel supply.

Compare the 0w40 to the 5w30 specs below. They don't list the total base number (TBN) for the 5w30, but the M1 0w20 has a TBN of 8.5. Compare that to 11.3 for the 0w40. The highest I've seen (in Mobil 1 delvac 5w40 commercial) is 12. The TBN is a measure of the amount of additives in the oil. The more additives, the higher the TBN, and the longer you can drive on the oil. If you take lots of short trips, the additives get "used up" to neutralize the acid created from the water (by product of combustion) reacting with the oil. That's why when your engine is "warmed up" after about 8 miles of driving, all that moisture in the oil burns off, so you don't use up the additives as fast.

M1 0w40 specs:
----------------
Viscosity, ASTM D 445
cSt @ 40º C 78.3
cSt @ 100º C 14
Sulfated Ash, wt%, ASTM D 874 1.2
Phosphorous 0.1
Flash Point, ºC, ASTM D 92 230
Density @15º C kg/l, ASTM D 4052 0.85
Total Base Number (TBN) 11.3
MRV at -40ºC 26242
Viscosity Index 186
HTHS Viscosity, mPa•s @ 150ºC, ASTM D 4683 3.7

Mobil 1 0W-40 meets or exceeds the following industry specifications:

API SM/SL/SJ/CF X
ACEA A3/B3 X
A3/B4 X
NISSAN GT-R X


Mobil 1 0W-40 has the following builder approvals:
0W-40
MB-Approval 229.3 X
MB-Approval 229.5 X
OPEL Long Life Service Fill GM-LL-A-025 X
OPEL Diesel Service Fill GM-LL-B-025 X
BMW LONGLIFE OIL 01 X
VW 502 00 X
VW 505 00 X
PORSCHE A40 X

ACEA A1/B1, A5/B5
API SM, SL,SJ,EC,CF,CD
ILSAC GF-4




Mobil 1 5W-30 has the following builder approvals:

General Motors Service Fill GM4718M
General Motors Factory Fill GM 6094M
Ford WSS- M2C929-A
Chrysler MS-6395
Honda RWC
Honda / Acura HTO-06


Typical Properties

Mobil 1 5W-30

SAE Grade 5W-30
Viscosity, ASTM D 445
cSt @ 40º C 64.8
cSt @ 100º C 11.3
Viscosity Index, ASTM D 2270 169
Sulfated Ash, wt%, ASTM D 874 1.0
HTHS Viscosity, mPa·s @ 150ºC ASTM D 4683 3.09
Pour Point, ºC, ASTM D 5949 -48
Flash Point, ºC, ASTM D 92 230
Density @15º C kg/l, ASTM D 4052 0.80

 

Very informative post on M1 - thanks

 

+1

Look at that viscosity index on the 0W-40. Very nice!

Do you also like the Pennzoil Ultra/Platinum oils? They seem to be getting good UOA's.

Andrew