Advice on slowing down oil consumption:

[slug_bug]

My 2007 Dodge Grand Caravan with 3.8l engine has burned oil from the day I bought it used with about 30,000 miles on the odometer.It burned about a quart every couple of months or about 2000 miles. I've used various name brand conventional 5w-20's(spec'd); Castrol, QSGB, QS Defy, and MC Blend most recently. I've done 5k OCI's religiously.

Well, I made the mistake of putting in a jug of the QSUD 5w-20 synthetic that I picked up for 97cents after rebate from WM. Now it's using oil at the rate of a quart every 1000 miles! There are no leaks.

I'm going to replace the PCV valve today to see if that helps slow down the usage. I'm planning on going to a 30 weight oil next OCI (probably year round). This leads to two questions?

1) I don't want to dump the QSUD early, there's only 1K on it. It's down a qt. right now. What should I supplement it with to slow down the consumption 10w-30, 10w-40? Syn or Dino?


2) The odometer is at 97k now. Is there a conventional oil I can use at the next OCI thats better at slowing down oil consumption?

Thanks for your comments.

 

[Phishin]

You could put a quart of QSUD 10-40 in it now. Maybe go ahead and buy two quarts and add one, and when it's low again, add the other.

Run that oil out to 5-6k miles and then you can add 5w30 as the third and fourth quart if needed.

 

[147_Grain]

10W-40 dino oil - even the least expensive Walmart brand will show an improvement over the 5W-20.

 

[danthaman1980]

Originally Posted By: Phishin
You could put a quart of QSUD 10-40 in it now. Maybe go ahead and buy two quarts and add one, and when it's low again, add the other.

Run that oil out to 5-6k miles and then you can add 5w30 as the third and fourth quart if needed.


^^^What he said.

Try 5W-30 next oil change.

 

[440Magnum]

If it were me, I'd just start using a good 5w30 oil as the make-up oil as it consumes the 5w20.

For what its' worth, I don't believe the oil is going past the rings or valve guides or any other wear part of that engine- the 3.8 is a brute and doesn't tend to wear like that. I blame the PCV system, so you made a good call on the PCV valve. But it may be more than just the PCV valve itself. It seems like Chrysler cars (FWD vehicles in particular) from the mid-2000's have PCV systems that are very prone to inhaling oil mist or droplets rather than just the vapors. Poor separation or baffles in the valve cover? Bad routing of the PCV hose? I don't know. Even the Hemi v8s in the rear-drives did it somewhat in 'spirited' driving, and Chrysler took a BIG swing at reducing it in the 2011-up Hemi v8 engines by putting a large oil trap right under the PCV valve to prevent it from snorting liquids. I also know that putting an oil trap that catches liquids from the PCV hose when the engine is running and then lets the oil drain back into the valve cover on wifey's 2005 PT Cruiser cut the oil consumption in a third or more. Other people put in PCV catch cans that don't drain back into the engine and they fill up with oil, so it still gets removed from the crankcase and has to be replaced. But at least that still keeps the oil out of the combustion chambers and reduces pinging and plug fouling.

Here's the trap (made from a cheap in-line fuel filter) that I made for the PT:

 

[Kuato]

I'm with 440Magnum, PCV, and makeup oil/switch over to a 5w30 dino and see how that goes.

You could try putting in 10wXX, but that won't help at startup.

 

[slug_bug]

Thanks for the advice all!

440Magnnum: Thanks for the PCV Oil Trap/catch can info. I think I will try to implement something like that.

 

[Hyde244]

Good suggestions here - changing the PCV and swapping for a dino or part synthetic 5w30 would be a good first step to see if there is any noticeable change.

If not, you could go to a thicker 10w30 to see if that may reduce consumption.

 

[cb450sc]

My daughter has a 1998 Civic and lives in Florida. The car burned about one litre every 5000 km using 5w30. I put mobil 1 HM 10w30 in it the past couple of changes and found the vehicle burned less than 1/4 litre. The Civic has over 270000km on it.

 

[Topo]

Lubro Moly Oil Saver found at Napa. I seen it work, it's the real deal. It won't increase viscosity either.