Engine Oil Disappears

[Rmack57]

I have an 07 Ram 1500 with the 5.7 Hemi. I bought this truck used about 5-6 years ago. I believe it had around 120-130K miles on it with two to three owners. It now has almost 180K. Truck was well taken care of by the previous owners. After I purchased it I notice it came up around a quart low after about 1200-1500 miles. I usually stick with basic castrol gtx due to this problem and change every 3K miles. I’ve researched it over the years and determined it’s the MDS programmed into the truck causing the issue. I’d like to see if there is anyone having the same issue and see if they did anything to fix it or they just live with it like i have. Note my truck does not smoke. I have had people follow me while I stomped on it and pull from a dead stop. Thanks

 

[Fast69Mopar]

I have an 07 Ram 1500 with the 5.7 Hemi. I bought this truck used about 5-6 years ago. I believe it had around 120-130K miles on it with two to three owners. It now has almost 180K. Truck was well taken care of by the previous owners. After I purchased it I notice it came up around a quart low after about 1200-1500 miles. I usually stick with basic castrol gtx due to this problem and change every 3K miles. I’ve researched it over the years and determined it’s the MDS programmed into the truck causing the issue. I’d like to see if there is anyone having the same issue and see if they did anything to fix it or they just live with it like i have. Note my truck does not smoke. I have had people follow me while I stomped on it and pull from a dead stop. Thanks

If you do not have any visual oil leaks and you are filling the engine with the proper amount of oil at each oil change interval then there is only one place for the oil to go and that is out through the exhaust.

Just because you do not see a woosh of smoke from the tailpipe doesn't mean the oil is not being burned in the catalytic converters. Oil consumption can be very subtle. You may never see smoke. The exhaust smell will change though.

What is the condition of the PCV valve? Is it operational? If the PCV valve is stuck or has a restriction it will allow excessive oil consumption.

You can do a cylinder leakdown test to determine if you have excessive blow-by in a particular cylinder.

 

[ST-8]

If you do not have any visual oil leaks and you are filling the engine with the proper amount of oil at each oil change interval then there is only one place for the oil to go and that is out through the exhaust.

Just because you do not see a woosh of smoke from the tailpipe doesn't mean the oil is not being burned in the catalytic converters. Oil consumption can be very subtle. You may never see smoke. The exhaust smell will change though.

What is the condition of the PCV valve? Is it operational? If the PCV valve is stuck or has a restriction it will allow excessive oil consumption.

You can do a cylinder leakdown test to determine if you have excessive blow-by in a particular cylinder.

I need to do this with mine, I lose about 3qts @5k miles. But now that it gets driven about 3k miles a yr, so I forget about it.. I need to start piecing together another heart for my pos

 

[justin13703]

The mds has nothing to do with oil consumption. If it is going away and it’s not leaking or ending up in the coolant, it’s burning it.

 

[Rmack57]

If you do not have any visual oil leaks and you are filling the engine with the proper amount of oil at each oil change interval then there is only one place for the oil to go and that is out through the exhaust.

Just because you do not see a woosh of smoke from the tailpipe doesn't mean the oil is not being burned in the catalytic converters. Oil consumption can be very subtle. You may never see smoke. The exhaust smell will change though.

What is the condition of the PCV valve? Is it operational? If the PCV valve is stuck or has a restriction it will allow excessive oil consumption.

You can do a cylinder leakdown test to determine if you have excessive blow-by in a particular cylinder.

I had the plugs replaced by an individual at 135-140k, the mechanic has been doing this for 30+ years, the plugs didn’t show signs of burning oil. Nothing out of the ordinary for what a plug should look like after 135K miles. Note the plugs were original and never replaced according to the mechanic. I replaced the PCV valve about 2 years ago. I stick to 5W-20 Castrol 7 quarts and a mopar oil filter. I’m sure it’s coming out of the exhaust I’m just looking to see if anyone is having the same issue.

 

[Rmack57]

The mds has nothing to do with oil consumption. If it is going away and it’s not leaking or ending up in the coolant, it’s burning it.

Well research so far that I have done and comparing thus far the MDS can only be the reason. I have no leaks, replaced my water pump 3 years ago no signs of oil in coolant, no large amounts of smoke coming out of the tail pipe what else could cause it??? Obviously MDS isn’t causing large amounts at one time but over a period of time like 1200-1500 miles in a 3k oil change.

 

[Dodge 1500 4X4]

Its not your MDS, you have either worn piston rings of bad valve seals, do a leak down test followed by a compression test do a dry test first record the psi and do a wet test, if you got a oil gun squirt 2-3 pumps in the cyl and see if your reading go up, ideal is 20% from the highest reading they should be 130-150 psi.

 

[OCDTech]

MDS shuts the cylinders trapping what fuel air is in there, keeping it there as long as its staying active, when it deactivates it goes back to running like a regular 8 cylinder vehicle. The system can't use or burn oil.

If your thinking that the 4 cyl that deactivate during this being worn more than the other 4 do the compression test and verify. Even though they are deactivated they are still "pressurized" in a manner of speaking so wear should be similar to the other 4.

 

[Dodge 1500 4X4]

Hay, Man don't know where you live but I've tried using a straight grade motor oil like 30w non detergent, It worked for me give it a try sounds like your engine is getting tired.

 

[Octane]

Ive had sbc engines with valve seals so bad that it would get 200 miles to a quart of oil.Never hurt a thing as it just lubed the upper cylinders a bit and burned off carbon deposits. Lol

 

[Fast69Mopar]

Hay, Man don't know where you live but I've tried using a straight grade motor oil like 30w non detergent, It worked for me give it a try sounds like your engine is getting tired.

I agree with this post. If you are not seeing any smoke at any point in time then I suggest switching to a different grade of engine oil like a straight grade 30W. The 5W/20 is a pretty thin oil. Your motor may have some cylinder wall wear or some piston rings that are showing signs of wear and is allowing the thin 5W/20 engine oil to make it past the rings. The next step up to a thicker straight grade 30W or even a 10W/30 may be the ticket.

Like the earlier poster stated, I would perform a cylinder leakdown test. This test will show you where the problem is coming from. With compressed air in the cylinder you will find where the air is escaping. It will be coming from the exhaust pipe (exhaust valve/seat leak), throttle body (intake valve/seat leak) or the rocker covers (piston ring/cylinder wall).

 

[Marley]

What's wrong with a little oil consumption ?
Had a Subaru burn that much and continue for another 200K.

Unless is a busted ring and eventually all cylinders will follow suit, mine did on a Chrysler new Yorker.

 

[dude22573]

I have the same oil consumption and have around 120K miles on mine. 5w-20 conventional oil right now and I add a qrt every 1K miles. I tried running a 5W-20 synthetic blend and the oil consumption got a lot worse. I am going to try 5W-30 on my next oil change and see what that does for the consumption. I have heard of people disabling the MDS on these trucks and allegedly eliminating oil consumption. Who knows if and why that would work... I have never owned a vehicle that did not consume oil so it really does not bother me too much. Oil is cheap and I may total the truck in a month or two, things happen. I just add a qrt every month and keep trucking.

 

[El Huapo]

I have an 07 Ram 1500 with the 5.7 Hemi. I bought this truck used about 5-6 years ago. I believe it had around 120-130K miles on it with two to three owners. It now has almost 180K. Truck was well taken care of by the previous owners. After I purchased it I notice it came up around a quart low after about 1200-1500 miles. I usually stick with basic castrol gtx due to this problem and change every 3K miles. I’ve researched it over the years and determined it’s the MDS programmed into the truck causing the issue. I’d like to see if there is anyone having the same issue and see if they did anything to fix it or they just live with it like i have. Note my truck does not smoke. I have had people follow me while I stomped on it and pull from a dead stop. Thanks

An easy old-timey way to see if oil is leaking by anywhere if you have no tools for a compression or leak-down test is to take it up a long grade and then coast down, touching the throttle as little as possible. When you have coasted for a long time, gun it. The cylinders will have pulled in the oil (if it has any real compression left) and when you gun it, the smoke will happen.
Now that worked on the older cars, I think it should work on the newer ones even with cats. I think it was "White smoke = water, black smoke = gas, blue smoke = oil".