Typical Average MPG unmodded?

[piper109]

If you are going to do an oil change, you would need to buy 2 gallons jugs of oil because many buy oil that way rather than buy individual quarts.
I believe its actually close to seven quarts needed. The D24T oil pan has a large reservoir where the oil pump pick-up is.

There are other cars out there that use much bigger oil pans than that.
Actually I like to keep the oil level about 1/4" above the full mark in winter as the engine rattles less on startup (probably piston slap is reduced).

Steve

[Jason]

The owner's manual lists the engine capacity at 7.5 qts with filter change. I always just dump in two gallons. I too keep the engine a little over full. The higher level helps the engine get oil pressure more quickly on startup. Less run time without oil pressure is less engine wear!

As for winter weather start up rattle??? Ha ha mine sounds like a rock tumbler going ouside, and thats running 5w-40! I can't immagine this thing running with 15w-40 at 15 or 20 degrees!

Jason

[piper109]

Yebbut...thats because you have the IP timing a bit north of the book value

Steve

Originally Posted by Jason

As for winter weather start up rattle??? Ha ha mine sounds like a rock tumbler going ouside, and thats running 5w-40! I can't immagine this thing running with 15w-40 at 15 or 20 degrees!

Jason

[Jason]

Really I'm not all that much over advanced, I backed it off so I wouldn't blow the head gasket (hopefully). I'm only running right at 1.0 or just above.

Jason

[RLDSL]

Originally Posted by Josh

Except for those of us that drive 3000 miles every month and a half ... I drive from Eugene to Portland and back just about every weekend. $100 is quite a lot to have to spend every 2 months or so. I'm at 3300 miles on this change so far and I'm hoping I can just afford an oil change before January when I get my next installment of money from school..

I don't quite get it. Why would you need to change that stuff in only 2 months if you are only driving 6000 miles? You'd be throwing away perfectly good oil. Unlike Mobil 1, this stuff is actually RATED for 25000 miles in a diesel and if using the Amsoil filter, it's rated for the same . They have recently been forced to downgrade change intervals for diesels across the board, but these new low figures do not apply to our older engines, this is only due to these newfangled modern computer controlled diesels that are having a bad problem with fuel dilution . They've been finding that all that fancy multiple firing per stroke has been leading to a lot of unburnt fuel finding it's way past rings and it's leading to premature lubricant wasting due to fuel dilution , but that has nothing to do with our old beasts, the old 25000 mile change interval still applies. That would get you about 8 months on a change, and if you installed a bypass filter on it, you could leave the same stuff in there for years, just send a sample in once a year for testing to make sure everythings OK.

[Jason]

I would have to agree, unless you are running a bypass soot filtration setup. By the time you buy all that crap, you could have just changed the oil anyway for the same or less money. Its the lifeblood of the engine, I don't get why people always want to push the limit on change intervals. Its not that expensive! Just change the damn oil!

Jason

[v8volvo]

Originally Posted by ForcedInduction

25k miles is too long for ANY diesel engine, especially a high emissions IDI engine. You must do an OA to determine the soot load your engine puts on the oil to know how long its safe to use the oil.

The oil brand, type and weight doesn't matter, none of it changes the soot deposit rate of the engine. Once it gets to 4% load, you're putting the engine bearing's life on the line.

Don't fully agree with you here. Different oils have different degrees of ability to hold soot in suspension. For instance, if you were using a gasoline-engine oil in your diesel you would have a very limited oil life due to those oils' not being designed to deal with diesel soot deposits. Conversely, if you are running a high-quality diesel-rated synthetic oil, and your car is running properly (aka cleanly with good compression and injectors) and you are not blowing black smoke like a tire fire at all times (Jason's car need not apply ), and you are using modern ultra-low-sulfur fuel or better yet biodiesel or some blend of the two, AND you are using the engine as it was designed to be used (longer-distance driving, long periods of running at operating temp, not quick hops around town), AND you are using a high-quality filter, I see no reason why your oil should not last 20-25,000 miles.

If you are not following the above directions, though, then even changing it every 3000 miles may not be enough to protect your engine from premature wear. I think with diesels the engine's long-haul longevity and health have as much or more to do with the pattern of how they are used as how they are maintained. You can have one that had the oil changed every 2500 and all maintenance done by the book that is completely worn out by 100k, or you can have one that had the oil changed every 10,000 and the maintenance slacked off a bit, but driven on the highway, and still running strong at 300k. All depends on the pattern of how and when it was driven.