Excessive Oil Consumption

PDX_Doug · 01-10-2008, 11:25 AM

Hey all!

I'm having a problem I can't seem to pin down. Hopefully some of the expertise here will provide some insight. To set the stage, I have an '04 Titan LE Crewcab. It is my daily driver, as well as the tow vehicle for my 28 foot (7,000#) travel trailer. About 54,000 miles.

Last summer, we took a major trip with the trailer down to Zion N.P. in Utah. The test was the biggest yet for the Mighty Titan. Over 3,000 miles total, ambient temperatures rarely below 100 degrees (as high as 115), and elevations reaching 9,000 feet. All towing a fully loaded trailer.

As always, the truck performed exceptionally well. Easily keeping up with the 'oil burners' we were traveling with in the mountains, etc. Everything was great, that is until we were about a two miles from home and noticed the oil pressure gauge briefly dropping to zero at each stop light. When we pulled up to the house, I immediately checked the oil level, only to find it was down 4.5 quarts! YIKES!!!

It should be noted that the Titan has never experienced any oil consumption in the past, and had been fully serviced (including - thankfully - Mobil1 synthetic oil) a week before we left. During the service, I had an injector cleaning, and in the process the dealer managed to cook one of the catalytic converters. That was replaced the day before we left. Now, before you say it, I know... I screwed up, and should have kept a better eye on the oil level during the trip, but as I said, consumption had never been an issue in the past, and it had just been fully (and expensively) serviced for the trip, so it really didn't enter my mind. I know better now!

Since that time, the truck has run pretty much okay. No obvious bad effects. It doesn't really seem exactly right, but I am also hypersensitive to it's condition now, so...? It also has not had any more issues with consumption, which I have been checking every couple of weeks, until just this last week when I discovered it down about 1.5 quarts again.

The rub is, I can't determine where the oil is going. There are no visible leaks on or under the engine, and no puddles in the driveway. There is also no visible smoke from the exhaust, or abnormal soot in the pipe. Obviously this is a substantial concern, as it could portend larger ($$$) issues down the road. We are also planning another similar trip this coming summer, and my confidence in the truck is shaken. The dealer is - at this point - blowing the whole thing off, and suggesting there is nothing they can do short of a very expensive engine tear down, and even that may not expose anything.

So the question is (thank you for your patience), what's going on here? Anyone else have a similar experience? I'm a fairly adept mechanical guy, but I'm at a loss on this one.

Thanks in advance for any insight you can offer,
Doug

BayStateSuks · 01-10-2008, 11:29 AM

4.5 quarts low? Holy hydrocarbon loss batman! I wouldn't think you could actually burn up that much oil, or if you did the engine would seize from lack of oil (only about 2 quarts left in the engine) and the remaining gunk left behind. In addition, it is really tough to burn up synthetic oil.

Could it be it was low when you started the trip, i.e., they did not put enough in there when they changed it? Seems to me that is is either leaking somewhere or enough wasn't put in in the first place.

I would say change the oil and make sure it is filled with the appropriate amount. Then monitor periodically.

If it is burning that much oil, I would be concerned that the cats may be getting damaged.

**Blackbeauty** · 01-10-2008, 11:40 AM

If it's "burning" that much oil, you'd be smoking blue out the tailpipe. And there'd probably be a greasy oily residue on the right rear under fender.

How are your other fluids? Tranny fluid look and smell ok? Coolant the right color and scent? If it's not burning it or leaking it (visibly, anyway), it's going somewhere. My guess is into one of the other fluids via some internal hole or gasket that's not stable.... I seem to recall something like this happening before, but can't remember any of the details or where exactly I saw it.....

**blavis** · 01-10-2008, 11:50 AM

Quote:

Originally Posted by Blackbeauty

If it's "burning" that much oil, you'd be smoking blue out the tailpipe. And there'd probably be a greasy oily residue on the right rear under fender.

How are your other fluids? Tranny fluid look and smell ok? Coolant the right color and scent? If it's not burning it or leaking it (visibly, anyway), it's going somewhere. My guess is into one of the other fluids via some internal hole or gasket that's not stable.... I seem to recall something like this happening before, but can't remember any of the details or where exactly I saw it.....

Take a good look at the condition of the engine coolant. You may want to drain a little bit out of the bottom of the radiator to get a good sample.

I hope all of this works out for you.

jiggadog · 01-10-2008, 12:39 PM

did you check the oil level after the change?

as mentioned, keep an eye on exhaust color (mind you, until your cataytic converter is cooked, you probably won't see a lot) and check for coolant on your oil filler cap. if you aren't experiencing any changes in oil level, i'd guess it was the dealer, if it continues..head gasket.

kman · 01-10-2008, 02:06 PM

if its not burning it then it has to be leaking it (either internal or external). You checked everywhere? pulled the skid plate off? checked the rubber hoses around the oil filter? (that is one design feature of this motor i don' like at all) Oil filter seal? Oil Pan seal? Oil plug seal? Pull all your spark plugs out, are they brownish grey or black and sooty? Check for leaks around the valve cover gasket? Check for crank shaft end bearing seal leak? (around the front pully, and transmission bell housing)

Good luck and keep up posted.

**Quartz** · 01-10-2008, 02:14 PM

Quote:

Originally Posted by blavis

Take a good look at the condition of the engine coolant. You may want to drain a little bit out of the bottom of the radiator to get a good sample.

I hope all of this works out for you.

I second this suggestion. I used to have a Jeep that pumped oil into the collant because of a small leak in the head gasket.

BayStateSuks · 01-10-2008, 02:24 PM

Certainly this much oil disappearing into the coolant from a head gasket leak would be pretty obvious I would think.

37L1 · 01-10-2008, 02:31 PM

Cooking the cat is a red flag to me. How did the service manager do it, when did he realize he did it? Was it driven after the cat failure and before the replacement?

If the engine inhaled some of the contents of your cat you may have a major problem starting from there.

Hope I'm way wrong.

**Quartz** · 01-10-2008, 02:35 PM

Quote:

Originally Posted by BayStateSuks

Certainly this much oil disappearing into the coolant from a head gasket leak would be pretty obvious I would think.

Good point. If I had half a brain I would have thought of that.

PDX_Doug · 01-10-2008, 03:04 PM

Thanks for the help guys! A couple of reply comments:

I did not check the level after picking the truck up from the dealer. I assumed (never smart) that a Nissan dealer could handle an oil change.

The thought that not enough was put in in the first place has crossed my mind more than once. Of course there is no way to prove that, but the thought that I headed off with my family into the desert southwest in July scares the bejessus out of me! And the dealer did know I was going to be doing just that.

I have always run premium lubricant in the vehicle because of the towing it does. Change the synthetic oil every 3K miles, and the tranny and diff fluid twice a year.

I will look again, but have not seen any indication of oil in the coolant, or visa versa.

There is absolutely no trace of oil on the exterior of the engine.

The burned up cat was not discovered until I got home from the tune up. That evening I went out, and the truck really started running awful, accompanied by a loud 'rattle' from up front. I have a friend that is a Chevy mechanic, and as soon as I mentioned the injector cleaning to him, he pegged it as a bad cat. The dealer claims there is no evidence the engine ingested anything, but of course they are suspect at this point.

37L1 · 01-10-2008, 03:16 PM

Quote:

Originally Posted by PDX_Doug

Thanks for the help guys! A couple of reply comments:

I did not check the level after picking the truck up from the dealer. I assumed (never smart) that a Nissan dealer could handle an oil change.

The thought that not enough was put in in the first place has crossed my mind more than once. Of course there is no way to prove that, but the thought that I headed off with my family into the desert southwest in July scares the bejessus out of me! And the dealer did know I was going to be doing just that.

I have always run premium lubricant in the vehicle because of the towing it does. Change the synthetic oil every 3K miles, and the tranny and diff fluid twice a year.

I will look again, but have not seen any indication of oil in the coolant, or visa versa.

There is absolutely no trace of oil on the exterior of the engine.

The burned up cat was not discovered until I got home from the tune up. That evening I went out, and the truck really started running awful, accompanied by a loud 'rattle' from up front. I have a friend that is a Chevy mechanic, and as soon as I mentioned the injector cleaning to him, he pegged it as a bad cat. The dealer claims there is no evidence the engine ingested anything, but of course they are suspect at this point.

I would do a compression check. . . there have been engines ruined by cat failure. Also a chance to look at the plugs.

*F150_Convert* · 01-10-2008, 03:32 PM

Quote:

Originally Posted by 37L1

Cooking the cat is a red flag to me. How did the service manager do it, when did he realize he did it? Was it driven after the cat failure and before the replacement?

Does a cooked cat taste better than other kinds of road kill????

BayStateSuks · 01-10-2008, 04:21 PM

Quote:

Originally Posted by PDX_Doug

Thanks for the help guys! A couple of reply comments:

I did not check the level after picking the truck up from the dealer. I assumed (never smart) that a Nissan dealer could handle an oil change.

The thought that not enough was put in in the first place has crossed my mind more than once. Of course there is no way to prove that, but the thought that I headed off with my family into the desert southwest in July scares the bejessus out of me! And the dealer did know I was going to be doing just that.

I have always run premium lubricant in the vehicle because of the towing it does. Change the synthetic oil every 3K miles, and the tranny and diff fluid twice a year.

I will look again, but have not seen any indication of oil in the coolant, or visa versa.

There is absolutely no trace of oil on the exterior of the engine.

The burned up cat was not discovered until I got home from the tune up. That evening I went out, and the truck really started running awful, accompanied by a loud 'rattle' from up front. I have a friend that is a Chevy mechanic, and as soon as I mentioned the injector cleaning to him, he pegged it as a bad cat. The dealer claims there is no evidence the engine ingested anything, but of course they are suspect at this point.

I bet here is what happened. Oil change tech drained oil and changed filter (maybe). As he started to put oil in he got a text or was paged. Stop and answer text and/or page, pull up pants, maybe check self in the left side mirror. After all of this activity, he forgot what he was doing, closed the hood and sent it out on its way.

Yahooligan · 01-10-2008, 04:29 PM

Just a quick comment about not adding enough oil to begin with...

Had this been the case I would have expected the OP to notice the oil pressure gauge dropping to zero from the beginning, not as he was just finishing a very long trip.

The only way I see this as the cause is if there are 2 things going on:

1) The oil was low to begin with, but not low enough to trigger any signs
2) There was enough oil consumption to drop the oil level enough to cause oil pressure problems.

Seeing as he didn't have any oil consumption before his trip then #1 would have to cause #2, I don't see how it's possible the oil started out low AND an oil consumption problem came up within such a short period of time.

Based on knowing the cat died and the other cases of this causing engine damage, one would have to assume that's what happened here. Scoring on the cylinder walls due to debris will definitely cause problems without being bad enough to really notice while driving.