Crap! Oil Sludge

hate to break it to ya, but synthetic oil can sludge too.

Sure if you literally run your truck into the ground and change the oil once every 3 years.
You would really have to abuse your oil to get good 100% synthetic to sludge.

You can change petroleum at 3000 religiously and it can sludge in some engines.

Huge difference.
 
Sure if you literally run your truck into the ground and change the oil once every 3 years.
You would really have to abuse your oil to get good 100% synthetic to sludge.

You can change petroleum at 3000 religiously and it can sludge in some engines.

Huge difference.

Ya no.
 
Believe what you wish, I will stick to the facts.

Fact: mines the biggest. :girl:

i had to make a joke. but i would agree with the other guys to buy a used engine and throw it in there. also if not sea foam, check into BG products for engine cleaners.
 
Believe what you wish, I will stick to the facts.

Facts are pretty ambiguous on this issue. There are plenty of 4Runners out there with over 200,000 all on standard Toyota approved car oil AND no sludge. It's apparent there no sludge because the engine has been opened up for various reasons (head gasket) and no sludge to be seen.

My truck had no sludge visible at all when it was opened up due to a head issue.

You aren't at 200,000 miles yet and synthetic won't prevent your heads from going bad due to normal wear and tear.
 
I am. The 2UZ takes 6.5 quarts of oil. I put 9 oz of sea foam and then top off with oil to the full mark.

Do you do this every oil change?

I will be honest I haven't been super diligent in my OCI's. I want to do a seafoam cleanse but was not sure how it worked. This helps a ton!
 
Believe what you wish, I will stick to the facts.

You made it sound like synthetic oil is made from ground up unicorn horns or something. Do I think synthetic oil is fluff in a street driven, low revving street truck motor? Yes. Do I think it's superior to conventional oil? Yes, but you typically only see benefits in high rpm race applications where constant heat is a problem.
 
This sludge has the same consistency and texture as Grease. It is thick and slippery.
 
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Do you do this every oil change?

I will be honest I haven't been super diligent in my OCI's. I want to do a seafoam cleanse but was not sure how it worked. This helps a ton!

Yes. I will pull the valve cover off in another 10k to follow up with the progress.


For what it is worth. The sludge is more like a jelly. There is nothing gritty or crusty about it. It is pumpable. So if you did do a motor flush with a cleaner. It would dissolve the oil jelly and resuspend it in solution.

Just keep an eye on the oil light. If it comes on, stop and drain the oil, refill and continue to flush.


I have done a lot of research on the subject. Sludge is caused short trips. IE People that live really close to work or school. The motors do not get hot enough the evaporate any moisture that might have condensed in the motor over night or through the combustion process itself.

When your engine is cold, the emission control stuff does not work very well. And a lot mot of the combustion byproducts gets through the rings. The block and rings aren't at operating temperatures to form a perfect seal. Combustion byproducts include H2O, Unburned Hydrocarbons, Carbon Monoxide, Nitrogen oxides and sulphur.

Sludge can happen with synthetic or Dino oil.

Some say the sludge is more prevalent in paraffin based oil such as Quaker State or Penzoil but it might be that it happens more often with those because it is cheaper and used more often.

Some say that if the engine gets to hot, it happens. The only problem with this scenario is that oil does not break down before the engine would overheat so this theory is thrown out. Now Turbos, right after the motor has been shut off will cook the oil at the turbo if it has been run hard. The substance that it left is hard and crusty. This is where synthetic oil really shines. It has a much higher operating temperature.

Long oil change cycles might cause sludging. But there are many semi trucks on the road that go 20k before oil changes. Mind you - They have 5 gallons of oil in their engines.

Some say that a plugged PVC valve is the culprit but that leads us back the short trips and not burning off any vapor. Once she is clogged up, It is no longer evacuating the crankcase vapors. When the vapors can't leave, sludge occurs.


Now there is always the perfect storm. IE - Short trips, using Quaker State, with 10K plus mile oil changes and a plugged PVC valve. This motor would be :censored:
 
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As Singtoe lamented above, that is why it is always a good idea to give short distance driven cars an Italian tune up at least once a month if not twice in order to prevent sludge from possibly forming.

That is why when looking to buy a used car owned by grandma or grandpa with low miles on it one should always try and get a visual inspection of the upper valvetrain to check for sludge.
 
Excellent info! I don't fall into the short trip category. The last 2 years it falls into the lucky to get 5k a year but before that it was 30k+
 
As Singtoe lamented above, that is why it is always a good idea to give short distance driven cars an Italian tune up at least once a month if not twice in order to prevent sludge from possibly forming.

That is why when looking to buy a used car owned by grandma or grandpa with low miles on it one should always try and get a visual inspection of the upper valvetrain to check for sludge.

italian tune up??? i changed the oil and as a preventive measure, i added sea foam to the mix. will run that for 500 miles and change again. maybe run 15w40 diesel oil to make sure nothing is in there. i haven't done the valve cover gaskets yet so i don't want any surprises when i do.
 
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What the crap. That's a chunk of oil sludge.

I don't remember what year Avalon it was, but it was bad. You could literally pull chunks of sludge off the valve covers and top end of the engine. Engine was replaced and came back with tons of mechanical problems (mostly in suspension, none in the engine) and it went to the scrapyard.
 
You made it sound like synthetic oil is made from ground up unicorn horns or something. Do I think synthetic oil is fluff in a street driven, low revving street truck motor? Yes. Do I think it's superior to conventional oil? Yes, but you typically only see benefits in high rpm race applications where constant heat is a problem.

So you think it is superior oil, it really doesn't cost anymore if you change it at longer intervals, so why not use what is clearly a superior oil?

I have seen clear benefits in virtually every vehicle I have owned since 1977, some much more than others.

The biggest was my old VW Baja Bug with an 2180cc suped up engine, it would always get hot and lose power when I ran it hard. I tried everything, deep sump, huge oil cooler and put it on the roof under a air scoop.
No change, tried synthetic one day and wham never over heated again no matter how hard I ran it even out in the desert, never loss power again.
Of course that was a suped up "oil cooled" engine but the benefits of synthetic oil were clear.
My wife's 1999 Lexus ES300, not only gets about 2-3mpg better mileage but those engines are notorious for sludging even if changing the oil at 3000.
Hers is clean as a whistle inside, it wouldn't be if we were using petroleum oil the past 13 years.


Yep "sludge CAN happen" with synthetic oil, but it is FAR more likely to happen with petroleum oil.
To get synthetic to sludge you either have to have a serious problem like coolant/water in the oil from blown gaskets or similar contamination or just never change your oil.

In a non contaminated engine you would really have to abuse the oil to get synthetic to sludge.
The longer drain intervals are nice especially if on a long trip you do not want to have to find some strange oil change place on the road to do an oil change.
My last trip was just under 8000 miles, I would never in a million years let regular petroleum oil go even 4000 miles let alone 8000.
When I changed it after getting home the oil still felt good, was dark obviously because that is what good high detergent oils do is clean and suspend, but I also don't think I burned more than a tablespoon. I kept checking my oil at every other gas stop but it never changed even a tiny bit on the dipstick.

Yet another benefit.

Obviously I am sold on synthetic oil and have been for 36 years now, but to me at least for obvious reasons that I have seen with my own eyes for decades.
 
So you think it is superior oil, it really doesn't cost anymore if you change it at longer intervals, so why not use what is clearly a superior oil?

I have seen clear benefits in virtually every vehicle I have owned since 1977, some much more than others.

The biggest was my old VW Baja Bug with an 2180cc suped up engine, it would always get hot and lose power when I ran it hard. I tried everything, deep sump, huge oil cooler and put it on the roof under a air scoop.
No change, tried synthetic one day and wham never over heated again no matter how hard I ran it even out in the desert, never loss power again.
Of course that was a suped up "oil cooled" engine but the benefits of synthetic oil were clear.
My wife's 1999 Lexus ES300, not only gets about 2-3mpg better mileage but those engines are notorious for sludging even if changing the oil at 3000.
Hers is clean as a whistle inside, it wouldn't be if we were using petroleum oil the past 13 years.


Yep "sludge CAN happen" with synthetic oil, but it is FAR more likely to happen with petroleum oil.
To get synthetic to sludge you either have to have a serious problem like coolant/water in the oil from blown gaskets or similar contamination or just never change your oil.

In a non contaminated engine you would really have to abuse the oil to get synthetic to sludge.
The longer drain intervals are nice especially if on a long trip you do not want to have to find some strange oil change place on the road to do an oil change.
My last trip was just under 8000 miles, I would never in a million years let regular petroleum oil go even 4000 miles let alone 8000.
When I changed it after getting home the oil still felt good, was dark obviously because that is what good high detergent oils do is clean and suspend, but I also don't think I burned more than a tablespoon. I kept checking my oil at every other gas stop but it never changed even a tiny bit on the dipstick.

Yet another benefit.

Obviously I am sold on synthetic oil and have been for 36 years now, but to me at least for obvious reasons that I have seen with my own eyes for decades.

Any reason not to switch to full synthetic mobil 1 now on a 97 w/ 140k miles that has always had Dino? I read conflicting information every time I look.
 
Any reason not to switch to full synthetic mobil 1 now on a 97 w/ 140k miles that has always had Dino? I read conflicting information every time I look.


Nope, I have switched to synthetic on every car I have ever owned without a single problem.
The only problem you could possibly have would be if your seals/gaskets have been fried/dried because of sludge from petroleum oil and the synthetic cleans it.
That could under certain circumstances cause a small leak, depending on how far gone the seals are it could also swell back up once it gets wet again from the synthetic oil.
Either way if any leak forms it is one you already had.
 

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