My anal nature has got me worried again.

Since the day I brought my LLY home, it has never used ANY oil, period.

I check my oil constantly, and now that I'm home from my 2500 mile trip to California, oil is down 4 "ticks" so that it now sits two "ticks" above the add mark. I know this isn't much oil consumption at all, but it still concerns me since it's out of the ordinary for this truck.

I tend to look for patterns with my vehicles, and this seems out of character for this particular engine.

The oil is Mobil Delvac 1 and it now has just over 4400 miles on it.

This was the first long trip I've taken with the truck, so I'm not quite sure what to think. It was run 14 + hours without shutting down several days in a row while on the trip, and most of this was cruising at 75-80 mph. One day I did 830 miles stopping only for fuel!

Anyway, what should I do? Is it anything to worry about?

P.S. Does anyone know how much oil I've actually lost, meaning how much oil is required to go from ADD to FULL?

This reminds me of a Chevy I owned long ago. It used very little oil running around town. Everytime I took it out on a long trip it used a quart going and none coming back. Very unusual. I finally figured out that it was an oil dilution problem. The short trips with choke on resulted in unburned fuel in the oil. I was in fact using oil and replacing it with gas so the level on the dip stick did not move. The long trip out heated the oil and boiled off the gas making it look like the motor burned oil only on trips going away from home.


Could a diesel do something like that? I don't know. Could one bad injector result in fuel in the oil? Again, don't know.

What I have found is that when I drive like there is a raw egg between my foot and the power pedal I get great mileage with this D/A truck

05 CCSB LT D/A

I did just have one injector replaced, but I don't think this is the problem. I really don't think that I was getting diesel in the oil all along and that was keeping my reading on the dipstick "correct."

http://www.dieselplace.com/forum/images/smilies/smile.gif what is 4 ticks low in terms of oil that needs to be added to get back to full?

IF it is not down to the add oil mark on the dip stick. I wouls say that is normal and good use of the oil. The oil is there for a reason and some always gets past the rings other wise it is not doing it's job.

An old timer told me "that a motor that does not use any oil must have something wrong with it!" so a few ticks down in 2500 miles is ok for highway driving. I agree at highway speeds and temps the motor oil gets cleaned out. Any water or other items in the crank gets cooked out.

A suggestion (if you have not already done so):

When doing a comparison, make sure the truck is parked in the same location (garage, driveway, etc) and checked when cold. This will minimize any variability in the measurement.

Yeah, I always check my oil with the truck sitting in the same exact spot with the engine completely cold. GM says in the owner's manual to check the oil 15 minutes after shutting down an engine at operating temp, but I always check when the engine is stone cold. As long as I'm consistent, I don't see why you would need to warm the engine first.

Assuming you have a boost gauge, take that little piece of tubing off where your boost gauge is mounted and see if there is any oil in there. I'm installing my gauges this weekend. I ordered Superdiesel's manifold and when I removed the original silicon tubing to install the manifold, I found oil in there coming down from the turbo.

I read in another thread (http://www.dieselplace.com/forum/showthread.php?t=27450) that the crankcase is vented into the turbo outlet somewhere and occasionally a little oil shows up. With such long runs, I wonder if you spit some of it out there.

Worth a check.

Sounds like you have everything covered. I made the comment about location from personal experience. If I check the oil in the driveway I get one reading, while in the garage produces another reading. Must be a slight variation in the grade.

Alright, I'll do that check Chisuzu. I don't have a boost gauge installed yet, but I can pull the silicone tubing you're talking about to check for oil there.

OC DMAX:

Thanks for the advice--I'm always willing to take all I can get! I've also found that with this particular engine, I have a hard time getting consistent readings for some reason. Even though I always check my oil with the truck in the same spot while stone cold, I get different readings a lot of the time. It does appear that I've lost at least some oil though.

That was my experience with synthetic oil. Went back to dino and no problem.

Jim

Ok, I went and checked, and sure enough, I have oil in the silicone coupler, and I also noticed a small area of residue at the end of the hose. It's definitely engine oil, so what should I do?

I'm assuming that this is where my "missing" oil went. I'm really not missing much, but could approximately 0.5 quart have ended up being blown into here?

I know I've read before that most engine experts agree that an engine will tell you where it likes to run. While I'm OK with my engine having it's own sweet spot, I just don't understand why it hasn't done this before now. Could it be that since I added more power and raised the boost pressure that this finally showed up?

Can any techs chime in?

That was my experience with synthetic oil. Went back to dino and no problem.

Jim
I am with you. I have also noticed more oil consumption in any vehicle of mine when running Synthetic. Not major, but enough that I notice it. I also noticed a little oil residue around my blue turbo hose with the syn, but not enough to "drip". I am changing my oil on Sunday, and it is back to 15/40 dino since we should be out of the below zero weather now...

This is interesting. I haven't been running Delvac for that long, and I've done short 4,000 mile intervals for the first few because I wanted to further remove any break-in material but still have all the cold weather benefits of the 5-40W Delvac.

Maybe since this is the longest interval I've tried so far with Delvac combined with my first long highway trip, this is just the first time I've noticed a little consumption. (But it's actually been happening all along?)

I'm kinda grasping at straws here--I'm just trying to take really great care of this truck I'm working hard to afford.

Ok, I've mentioned that I have a hard time getting consistent readings, so I drilled the dipstick like someone (sorry I can't remember who it was so I can't give proper credit!) on here suggested, and I'm getting much more consistent readings. I have definitely lost some, but probably not as much as I thought before.

Does anybody have the TSB for the crankcase venting?

Can anybody tell me how much oil it takes to go from "ADD" to "FULL"?

My LB7 with only 29,000 is burning about 2 quarts every 2000 miles its at the dealer right now and they say that nothing is wrong. Im starting to become a Cummins guy

I have noticed just the opposite with synthetic oils (with respect to consumption). My truck will go 5K miles and loose about 1/2 quart of oil (Delvac 1). On average, half of the miles are pulling a travel trailer, so the truck is working. From new to 10K miles, I was using Chev Delo 400. Typically, it was using 1 quart every 3k miles while the Del0 400 was being used. Just my observations, results will vary.

I have also noticed the same on my Toyota Camry commuter car where I use Mobil 1. Very low oil consumption.

I also drilled the oil dipstick when I first got the truck in Nov 2001. I could not get consistent readings. Another trick is to push the dipstick down until the bottom of the plastic handle hits the top ot the metal oil tube (sorry for the wording). This allows the dipstick to remain approximately 1/2 inch out. This helps to get an accurate reading when the engine is topped off with oil. It places the oil level in the middle of the reading area.

Coyotekid, IMO I think you should be asking Mile L. what he did with your missing oil. ):h Sorry, I just had to say that. :lol:
I wouldn't worry too much about the small amount for that trip. GM will say it's just normal. Just keep an eye on it.

That's what happened to it! Mike took it!

>>>headed back to Cali to kick some ass...>>>

How much oil do most of you guys use?

I know all engines are different, but I'm just trying to get a rough idea here.

Coyotekid,

I still say Mike L. took it when he was doing your Ally upgrade....):h

I have a total of 11K miles. During my first 7.5K my LLY used no oil.

During my recent 2.5K trip to Denver and back pulling my 9K TT, it used 3 ticks on the stick. I don't like that, but it's really not that much
and of course GM will say it's normal. I have also just recently noticied that I have some wetness at the intercooler outlet/hose connection. :(

My experience with oil is on extended runs at high rpm's when the engine is not used to it there is a small amount of oil consumed. I've had this with my old Saturn and Chevy 1500 truck. With my Saturn I used about 1/2 quart between SanDiego and Vegas (95deg weather going 90mph). I normally drove it around San Diego and not more than an hour on the freeway at a time. It used no oil in normal use. My truck used 1qt going from San Diego to Montana and 1qt on the way back. I was doing 80 to 90mph. Like the Saturn my daily driving around town it used no oil. I used valvoline synthetic in the 1500 and Valvoline dyno oil in the Saturn.

As far as how much oil to add I'd start with 1/4 quart and work your way up until you are at the full mark. It probably is more like 3/4 of a quart low but at this point you aren't low enough to do damage so filling is slowly to make sure you don't overfill it. Just my .02

Alright, thanks for the info guys. My oil consumption sounds very similar to both your experiences. Mine has never used any during my normal use, but I've never taken one continuous drive over about 250 miles in this truck before the trip to Cali. I think I'm totally fine.

I've always been the type that thinks a "good" engine absolutely can't use any oil, but I'm really changing my mind about this the more I research it. It seems like most of the "experts" agree that small oil consumption is even favorable in some cases.

I know OTR truck operators that consider a gallon of oil to even be considered small consumption since the sumps are huge on the big rigs.