July 21, 200718 yr Just wondering if anybody has experienced or knows of someone who has developed sludge in the motor or maybe a better question would be to ask if subarus are prone to sludgying like some other car manufactures
July 21, 200718 yr Just wondering if anybody has experienced or knows of someone who has developed sludge in the motor or maybe a better question would be to ask if subarus are prone to sludgying like some other car manufactures I have never heard or read that Subaru is prone to sludge (ala Toyata), but like any Engine, if neglected Sludge can occur.
July 21, 200718 yr No they are not prone to sludge. Also to prevent sludge change the oil more frequently. One cause of sludge is many short trips where the oil doesnt get a chance to warm up. It takes 2 - 3x's longer for oil to warm up then water. nipper
July 21, 200718 yr Subaru's are not prone to sludge. Any engine can sludge if the oil change interval is too long, or as nipper said if it doesn't get a good drive to get the engine oil up to operating temp (~180 deg. F) periodically, water condensation and fuel may build up in the oil. The 'sludge prone' engines frequently operate the oil at relatively high temps too which leads to sludge.
July 22, 200718 yr Subaru's are not prone to sludge. Any engine can sludge if the oil change interval is too long, or as nipper said if it doesn't get a good drive to get the engine oil up to operating temp (~180 deg. F) periodically, water condensation and fuel may build up in the oil. The 'sludge prone' engines frequently operate the oil at relatively high temps too which leads to sludge. An FYI http://www.autosafety.org/article.php?did=1090&scid=82 VW 1.8L and chrysler 2.7 as well as a saab engine all have sludge problems. Chrsyler is leaving people out to hang no matter what proof you have the car was well maintained. Thats why I alkways tell people to use the Harsh Driving intervals to change their oil. Some cars its a poorly designed PCV system. Most I think are too small an oil capacity. Less oil gets contaminated fairly quickly. nipper
July 22, 200718 yr Cool link nipper. Some excerpts... Bruce Crawley, a lubrication specialist for ExxonMobil Corp., said the first thing he would look for in investigating a sludge problem would be "cold spots" on surfaces where the oil circulates, because large variances in internal engine temperatures can cause sludge. ... According to General Motors, the industry standard for temperature differences between the cylinder head and engine block is between 10 and 15 degrees. ... Parry, who says he has repaired about 30 sludge-filled Toyota engines since 1998, contends the V-6's cylinder head temperature is too high because Toyota reduced the size of coolant passages in the head gaskets. ... Parry said he has measured the temperature of the cylinder block and heads. He said the block runs at 190 to 210 degrees Fahrenheit, while the heads typically reach 260 to 270 degrees. ... He says that makes for a hotter, cleaner burn, but also causes sludge to build up because the oil gets too hot. Also, Parry says, sludge develops as the oil passes back into the block, which is running 60 to 70 degrees cooler.
July 23, 200718 yr and who said you cant learn something new every day... very informative Yeah. My first reponse was going to be that engines don't produce sludge, poor maintenance and driving habits do. But seems like there are some engine designs that promote it. I stand corrected.
July 23, 200718 yr Yeah. My first reponse was going to be that engines don't produce sludge, poor maintenance and driving habits do. But seems like there are some engine designs that promote it. I stand corrected. You can sit you know. We are very informal here :-p nipper
July 24, 200718 yr VW 1.8L and chrysler 2.7 as well as a saab engine all have sludge problems. Chrsyler is leaving people out to hang no matter what proof you have the car was well maintained. nipper Which VW 1.8L? Do you have a link?
July 24, 200718 yr Which VW 1.8L? Do you have a link? there is this thing called google. It's wonderful. In other words, there is too much listed to post a link. Google vw 1.8 sludge and read. This is not the worlds best kept secret. nipper
July 24, 200718 yr The difference in the head temperatures were maybe 10% of the problem. IMO, it was the fact that the head was hot and there was only a 4 quart sump. Oil sees extreme temperature variations in alot of cars. Especially turbo'd applications. As we all know, turbos get fairly hot, especially the ones that don't have water cooling. You don't see every turbo'd vehicle sludging up. That said, I lean more towards inadequate sump capacity, and Subaru does a good job designing the sumps on just about everything. Heck, our H6's hold like 6 or 7 quarts of oil, do they not?
July 24, 200718 yr Not the ER27 (XT6 engine). It was under 5 qts. Nevertheless, and notwithstanding what factors one might think are the worst offenders in terms of cause, some engine designs are extremely poor in terms of beating up oil and causing sludge or coking or both. The issue is far larger than just sump capacity, though clearly a 15 gallon sump would help prevent the sludging in SOME of these applications (it would not stop the Toyotas from sludging, but may perhaps help one of the VW engines).
July 25, 200718 yr Most of the Toyota sludging problem is due to customers not changing the oil as often as they should, although Toyota will replace a a sludged 4 cylinder (5S and probably the 4S but not sure) and the V6 (Camry and Sienna engines) up to a certain mileage but I don't know the details. It depends on the amopunt of sludge, and the amount of cylinder damage whether or not you get the whole motor replaced, just the head, or if it just gets cleaned and new valve seals installed. We have a poster about it @ work but I haven't read it super carefully...
July 25, 200718 yr Sorry, Hondasucks, the Toyota issue is MOST DEFINITELY NOT JUST AN OWNER NEGLECT ISSUE, IT IS A DESIGN FLAW. There are WAAAY too many people with receipts for extremely short drain intervals and failed, sludged motors for even Toyota to claim otherwise. The primary reason Toyota is replacing engines under warranty is that they know they have a problem that's frankly huge. This is now far too well documented to claim otherwise.
July 25, 200718 yr Sorry, Hondasucks, the Toyota issue is MOST DEFINITELY NOT JUST AN OWNER NEGLECT ISSUE, IT IS A DESIGN FLAW. There are WAAAY too many people with receipts for extremely short drain intervals and failed, sludged motors for even Toyota to claim otherwise. The primary reason Toyota is replacing engines under warranty is that they know they have a problem that's frankly huge. This is now far too well documented to claim otherwise. Agreed. When you use the interval in the owners manual, you should be comfotable in knowing that your engine will be healthy. This is the fault of too little oil, and too long a maintaence interval. Professionally I dont buy they extreem differnce in oil temperitures. If that was true everyone with an external engine oil cooler would see the same thing. nipper
July 31, 200718 yr That's just what one of the techs told me... He's seen cars with the affected motors with 200k on them with no problems, and he's seen them come in with 60k that smoke real bad and have like 2" of sludge in the oil pan.... Could just as easily be dependent on what type of oil they were running, cuz let's face it not everyone goes to the dealership and pays $30+ for an oil change :-P (Although it's always great when we get a car that just came from Jiffy Lube that has a brand new oil filter on it, and the yellow seal paint junk on the drain plug, but no oil in the engine... Or when they first started putting the external spin-on filters on the automatic trannies, the dummies at Jiffy Lube liked to drain 4-5 quarts out of the transmission, and put 4 quarts into the engine... by the time they got to us they had a fried transmission and every seal in the engine blown... (Although it was sorta convenient since Jiffy Lube is right around the corner from the dealership I work at...)
July 31, 200718 yr or the class c mechanic at the dealership that never changed the filter and left the plug loose. Dealers are no better. nipper
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