1998 LS400 Oil Turns Dark Quickly

[Hokiefyd]

Originally Posted By: Gebo
Originally Posted By: Hokiefyd
I also think it's funny that people will respond with a "chill out" response, or "don't worry about it". Having a curious mind and wanting to know a reason for something is very different from worrying about it and thinking there's a problem.


Thank you for the last 2 sentences. ;-)


I will leave them in your quote for posterity, but I actually just edited them out of my reply! Ha ha.

I did re-read the original post asking what to check (as if to fix the oil-darkening problem). I think that's probably what the "don't worry about it" comments were keying-in on. I still believe that one can ask a technical question without being "worried" about something, but I also think I see the potential reason for some of the remarks, so I took that part out of my reply.

Cheers all.

 

[NextUpVeloster]

Originally Posted By: Oregoonian
In the 50 thousand mile I've owned the 03' Ford Focus, I've used the following oils'...all 5w20...all synthetic.... and all with an OCI averaging 7500 miles.

M1-EP
Valvoline Synpower
M1
PP

The M-1 EP was the first oil I used after purchasing the vehicle with 57K on the OD. It turned dark very quickly, doing a beautiful job in cleaning up the engine.

After using the above (M-1EP), all the above oils used stood fairly clear, turning to a dark amber when changed.

Based on the above, I don't think that the answer to why oil goes black after 2000 miles is...oil chemistry. I must be something else.


You just added variables into the question. You state that you started using an oil with a chemistry for cleaning at 57K.. and report it turned dark quickly. Seems the oil chemistry interacted with the engine internals in a way to carry more contaminants and darken it quickly.

The original question was to why the OIL darkens quickly, as you state yourself. Not what the engine does to it. Still that is the opposite side of the same coin.

The other oils, and their chemistry (*sum of all properties) seem to have had less to carry around, but still darkened at their own rates.

I do not think you adequately dismissed the oil chemistry answer. However, another poster introduced response of "the engine itself." That being the variable you introduced I would be fine with calling that the reciprocal property, since the oil goes in? The engine itself.

 

[dave1251]

Color change is a function of several things: additive package darkening, oxidation of basestocks, and amount of carbon in the oil.

Since all or most oils are dyed more or less, the amount and type of dye added may well affect how dark an oil turns.

Are a couple of simple answers and a possible observation.

 

[Hokiefyd]

Originally Posted By: dave1251
Since all or most oils are dyed more or less, the amount and type of dye added may well affect how dark an oil turns.


This is a great point as well.

 

[Gebo]

Originally Posted By: dave1251
Color change is a function of several things: additive package darkening, oxidation of basestocks, and amount of carbon in the oil.

Since all or most oils are dyed more or less, the amount and type of dye added may well affect how dark an oil turns.

Are a couple of simple answers and a possible observation.


I understand oil chemistry has a tremendous effect on the color of the oil. I am perfectly clear on this.

I must not be clear in my question. I am using the exact same oil and filter in 3 different vehicles and it only darkens quickly in one. My question is what about that particular Lexus V8 engine would cause this since the exact same oil doesn't do it in the other 2 engines? I'm not losing a lot of sleep as it has been doing it for 11 years. Just thought someone could explain it to me. I wouldn't think it is still cleaning the engine 140,000 miles later...

 

[dave1251]

Originally Posted By: Gebo
Originally Posted By: dave1251
Color change is a function of several things: additive package darkening, oxidation of basestocks, and amount of carbon in the oil.

Since all or most oils are dyed more or less, the amount and type of dye added may well affect how dark an oil turns.

Are a couple of simple answers and a possible observation.


I understand oil chemistry has a tremendous effect on the color of the oil. I am perfectly clear on this.

I must not be clear in my question. I am using the exact same oil and filter in 3 different vehicles and it only darkens quickly in one. My question is what about that particular Lexus V8 engine would cause this since the exact same oil doesn't do it in the other 2 engines? I'm not losing a lot of sleep as it has been doing it for 11 years. Just thought someone could explain it to me. I wouldn't think it is still cleaning the engine 140,000 miles later...


You have a engine that has the right combination of factors that change the color of your motor oil darker than others.

 

[Gebo]

Originally Posted By: dave1251
Originally Posted By: Gebo
Originally Posted By: dave1251
Color change is a function of several things: additive package darkening, oxidation of basestocks, and amount of carbon in the oil.

Since all or most oils are dyed more or less, the amount and type of dye added may well affect how dark an oil turns.

Are a couple of simple answers and a possible observation.


I understand oil chemistry has a tremendous effect on the color of the oil. I am perfectly clear on this.

I must not be clear in my question. I am using the exact same oil and filter in 3 different vehicles and it only darkens quickly in one. My question is what about that particular Lexus V8 engine would cause this since the exact same oil doesn't do it in the other 2 engines? I'm not losing a lot of sleep as it has been doing it for 11 years. Just thought someone could explain it to me. I wouldn't think it is still cleaning the engine 140,000 miles later...


You have a engine that has the right combination of factors that change the color of your motor oil darker than others.


lol...Dave, I'm up to speed with you. I'm looking for a deeper explanation. What are those "factors"? I guess the answer I'm looking for it too complicated or cannot be explained to my satisfaction. Maybe I'll take up drinking....not!

 

[Pablo]

Mostly caused by blowby.

 

[Gebo]

Originally Posted By: Pablo
Mostly caused by blowby.


If this were the case, wouldn't I see oil usage?

 

[Pablo]

Originally Posted By: Gebo
Originally Posted By: Pablo
Mostly caused by blowby.


If this were the case, wouldn't I see oil usage?


No, not really - blowby is combustion gasses headed into your crankcase.

 

[CharBaby]

I use the same exact oil(s) in both my '01 Lexus RX-300 1MZFE and my '04 Nissan Altima QR25DE per OCI.

The Lexus, to this day remains more clean looking even when ready for another OCI. I have gone 8 months/6K miles(not regularly), and shrugged my shoulders as to why I was changing the oil/filter, it looked so clean! This engine is supposed to the the "Sludge Monster"

OTOH, the '04 Nissan has always darkened within weeks of the OCI, and has since the day I bought it new. After 3 months/3K miles, the oil was so black, it made me feel as though I went too far! And this engine is supposed to be "Hard on Oil"

Same oil, 2 different engines. Doesn't matter which brand/wgt of oil I use but, it's the same oil for each car, per/OCI.

 

[ARCOgraphite]

Originally Posted By: dave1251
Originally Posted By: ARCOgraphite
Originally Posted By: Oregoonian
The question is.....WHY.

Does anyone have a reasonable answer?

I think GEBO has to tell us WHICH amsoil he's using. If its NOT the synthetic Longlife stuff AND the oil has high detergency it will be scavenging ringpacks and heads on overtime. I've noticed this darkening when trying group III high detergency "phoney" synthetics (Castrol Syntec) but not in the past with the real PAO AMSOIL trisyn M1 with high TBN/DP. Now LOW detergency group II will usually look cleaner on the stick but leave the varnish in the engine. Most GF-5/SN are high DP now due to turbo deposit TEOST requirements and other increased cleanliness with the new std. I'll prefer a slightly varnished engine with oil of better lubricity that a sparkling motor that runs like a box full of rocks.


You made zero sense. You stated that oil will clean while looking good on the dipstick yet will varnish the engine while cleaning the oil rings and heads. But does not provide sufficient protection, yet how many millions of vehicles are on the road right now with GF-5 oils, I do not see hoards of cars just spontaneous con-bursting on the highway. Your driving, maintenance habits or just plain old bad luck may destroy engines, but the overwhelming majority of the rest of us are not in the same boat. ARCO if the newest spec stuff is bad for your engines, just shop at K-Mart and clean out that GF-3 stuff, I even saw a Pennzoil PAO with Pennzane on the self. Ebay is a good place to buy the oil you are looking for also. But if you feel different please provide us with a scientific study on the matter why GF-5 levels of a particular anti-wear additive is destroying engines by the thousands, ZDDP is not the only one factor and not the only anti-wear additive because there is a symbiotic relationship between basestocks, detergent, and anti-wear additives. Because the overall make up of a motor oil is a whole lot more important factor than a individual part. The formulation of the motor oil for your car believe it or not is not inadequate for engine protection, because if it was inadequate there would be a lot of PCMO blenders out of business. Some may give you the sense of protection that you desire at a higher price point, and often you are paying for that sense of protection because it is a feeling nothing more.
Nice rant but you you addressed nothing properly in my post. Its well admitted by the industry that GF-5 is a compromise. The Cam wear allowances for PASS are obscene. My engine(s)run smoother and more powerfully with the oils and filters of my choice that happen to NOT be ILSAC oil. If I could easily get PU at a reasonable price ( I will add for GEBO, I made the (possibly incorrect) assumption that the oil was NOT darkening on a different oil blend. If one engine is acting differently It may well be improperly broken-n exhibiting poor ring seal (at PABLO) and/or poor tune in one or more cylinders (plug index, bad inj spray pattern, carboned intake valve heads, etc.)

 

[dave1251]

Originally Posted By: ARCOgraphite
My engine(s)run smoother and more powerfully with the oils and filters of my choice that happen to NOT be ILSAC oil.


For you I will buy that.