Can a conventional oil keep an engine..

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wtd

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as clean inside as a synthetic? When I recently had my intake manifold gaskets replaced on my truck, the mechanic said that the inside of the engine that he could see was spotless. I'm wondering if the Chevron Supreme, I recently switched to, will be able to keep the inside of the engine as clean as the Mobil 1 was doing.

Wayne
 
quote:

Originally posted by wtd:
as clean inside as a synthetic? When I recently had my intake manifold gaskets replaced on my truck, the mechanic said that the inside of the engine that he could see was spotless. I'm wondering if the Chevron Supreme, I recently switched to, will be able to keep the inside of the engine as clean as the Mobil 1 was doing.

Wayne


Really, no, even on 3,000 changes.

If it's an HDEO, then yes, but that's an unfair comparison.
 
This is the $64,000 question isn't it. How many miles on your truck wtd? From what I've found, it's somewhat difficult to find anyone who's run an engine out past about 150K miles on any oil...
 
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As long as you change it often enough it should. I had over 100k on my Lincoln, which my dad bought new, always a fresh dose of Valvoline
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and a Motorcraft filter every 3k. When it needed new head gaskets, common on the Ford 3.8 V-6, the dealer said it was clean as a whistle inside.
 
205,000 miles on my old subaru using dino oil.
when i rebuilt the engine, the insides were spotless.
the reason i rebuilt it was because of a leaking radiator which overheated the engine.
it would of had much more life past 205k, but the point of my post is to say that the insides of the engine, were yellow colour, a light yellow. there was not one bit of dark varnish or sludge after 205,000 miles.
this tells me that it isnt so much the base stock or brand of oil you chose that denotes if your engine stays clean inside, but the design of the engine.
many engines run fairly hot oil tempatures. i have seen people state here that they have seen 270 degree oil temps. this is bad to me.

i dont really care what anykne else says, i believe oil should be kept BELOW 212F, more like 170ish. any water in the oil will still evaporate at 170F, heck, water will evaporate at room tempature! why so many people say oil needs to be so hot? heat kills oil, and adding an oil cooler is one of the best things you can do to prolong the life of your engine.
i have to wonder is some of these so called sludge monsters, like certain toyota engines, are not so sludge prone afterall, but just have abnormally high oil tempatures which break down the oil quicker.
with more and more engines comming stock with oil squirters, the oil temps further increase.
 
I think the reason why the V6 Toyota's have the reputation for sludging is because of these high oil temps and lack of simple maintanance.
High temps can often lower emissions in a clean engine and also increase fuel economy.

3K/3M OCI is a good recommendation for these motors with an eye on the PCV system also.

BTW,Pearl Harbor,you have not been forgotten.
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I had an '88 Chevy S-10 that I bought new and used nothing but Pennzoil 10W-30 in it. After about 9 years, I replaced the valve cover gasket and the engine was clean after over 100,000 miles. Just a little film of varnish on the valve cover and rocker arms, but I'm sure this would not hurt anything. I think I'm gonna switch back to dino, but still haven't decided for sure. Hard to beat $1.08 per quart for Chevron Supreme at Wally World. I think the best quality of synthetic is that it keeps the inside of the engine spotless.
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crypto is on the right track, the engine sealing is the key. There is little inherent solvency in fuels or oils to compensate for blowby and the internal temps. The higher quality oils with a better add pack will attempt to maintain cleanliness better than the cheaper grades of lubes, now if the engine is good sealer and all other variables are the same it will remain relatively clean.

Having said that and accepting the ancedotal evidence posted, I rarely see a motor in analysis that is inherently clean using the cheapest lubes. Even if they are changed regularily.

There are ways to enable the cheaper lubes to work well and moderating the optimum oil temp is one key area.
 
Thanks for all of the replies. I currently have 58,800 miles on this truck. I will be using either Auto-RX or LC with the Chevron but was curious if a conventional by itself would keep things as clean.

Wayne
 
I cannot actually compare it to synthetic oil but, I have a 1987 Grand National with 120K on Castrol GTX 10W-30 dino w/Fram oil filter every 3-4K since new (Jiffy Lube). In spring of 2002 I replaced a valve cover gasket and oil pump and I can say that everything was so clean that I did not even have to spray it down as I expected. The valve covers are usually where the sludge will accumulate and there was NONE. The oil pan was just as clean and I did not even need to wipe it down. There was nothing at all in the oil pan, not even metal shavings as expected. I drove this car very hard for the first ten years or so.
 
The original question was "can a mineral oil keep an engine as clean as a synthetic".

Many of you have replied saying that your engine is "clean" with the mineral oil you are using, which is very good.

In regards to the question though...your engine is not as clean as it would have been if you were running a synthetic.
 
Since syns have better oxidation (burning) and vaporization qualities over dino, and often have increased detergents/dispersants as well, they have the ability to leave an engine cleaner both through their chemical structure and their additive package.

That said, many dinos have D&D packages which are more than sufficient to keep a majority of engines quite clean when oil is changed at reasonable intervals. I've never had any significant sludge buildup in any of my engines, with all but one of them using conventional, non-diesel oils. The one that used syn faired no better in terms of sludge/varnish. But all engines are unique, of course -- you can monitor your valvetrain through the filler cap and see just how well your Chevron is handling this over time, and make changes if needed.
 
I recently helped a friend pull apart a Toyota V6 that came out of a supercharged Tacoma the owner said it had regular changes with Castrol GTX, the motor had a very light varnish on all parts except for the pistons with has a good bit of carbon build up especially the upper rings, I guess in this motor that was the only place that got hot enough to degrade the oil, the question is would synthetic have done better? I assume so but don't really know for sure I have never seen pistons that were run on synthetic

it was replaced because of a knock, turned out a piece of one spark plug broke off and ate up one piston and the bottom of one head, it would have been a very good rebuild candidate if the mechanic that did the engine exchange had not left it outside for 6 months with the throttle body pointing up
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now all the intake valves and several piston bores are badly corroded

I have seen different parts of other motors (valve covers pans etc.) and the ones that run synthetics have all been spotless where I can see
 
A lot of this depends on the value of the vehicle. I have some old, high-mileage vehicles. I also have a truck with low miles. The daily drivers get whatever is on sale at Walmart. Lately I have been putting Supertech stuff in them. The truck gets the best I can find.

It is irrelevant if you use Mobil 1 or anything else if you wreck it or dies from rust or you don't think the tranny will make it another 100K miles.
 
To me, that's one of the biggest (if not the biggest) areas where running a synthetic or HDEO makes a difference.

Over time, from heat, contamination and shearing, the ring/ring area breaks down oil, and thus you end up with a good deal of deposits, and sometimes, stuck piston rings
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[ December 09, 2003, 08:24 PM: Message edited by: Jelly ]
 
quote:

Originally posted by RavenTai:
it would have been a very good rebuild candidate if the mechanic that did the engine exchange had not left it outside for 6 months with the throttle body pointing up
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now all the intake valves and several piston bores are badly corroded


Might still be usable with a little bit of TLC...
 
Be honest...how long do you plan to own your vehicle?

I have a 10 year old car with over 220 000 m; somedays I wish the engine would die, 'cause everything else is breaking. Unfortunately (fortunately?), the engine itself is in excellent shape, VERY clean under the valve cover and consumes little oil.

Heres a list of recent and upcoming repairs:

Clutch (3rd) chattering and beginning to slip
Distributor failed (2nd)
Coil
Ignitor
Starter
Multiple exhaust components
Heater fan (REAL! fun to fix...)
Brake pads (frt - 4 set)
FRT rotors ( 3rd set)
Cv boots
Outer tie rod ends
Frt brake caliper
Way too many tires...

PS - I love the car, a '93 Acura Integra. It has run a steady diet of synthetic oil, mostly M1.

SOMETIMES!!! I wonder if making the engine last so long is a good idea...???

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Not to be a naysayer, but I've run Mobil1 synthetic for reasonably short intervals the last 2 1/2 years. When I open my filler cap, I notice a thin film of brown scunge on the underside of the valve cover around the filler hole area...I think it's just a "low traffic area" so it stays there.

The engine is the infamous GM 3.4L Intake Gasket Monster, but so far no other indications that this is an abnormal condition.
 
Geeeman;
I posted my last before yours came up.

I've gotten little hints from my Chevy that the engine may well outlast the rest of the car by a long shot...to avoid your predicament I plan to run dino oil as long as the oil change light tells me to. I think it's programmed for the equillibrium point between the engine and everything else.
 
Matt, you may be getting coolent into the oil if you've got ANY visible crud in your 3.4L. I had a 99 Grand Am GT for a while and it had 5,000 mile drains of Mobil 1 and it was so clean inside the motor I could have eaten off of it. When sold at 60,000 miles on the odo, the buyer commented that the inside of the engine was spotless through the oil fill.
 
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