I have around 153,000 miles on it and it runs great, but I've noticed the last few oil changes that it can be low 1-2 quarts of oil. Last oil change was about 2100 miles ago and I bet I'm 1.5-2 quarts low. And they put in 7 quarts at the oil change.

It's not dripping any oil, and based on what I can tell it isn't smoking out the tailpipe like is burning oil either - nor do I get the smell like its burning oil!

Thoughts on what the cause might be or what to be checking?? Not sure if that is common on this engine with this many miles?

 

What type oil are you using? All my rides are 100K miles+ and are on high mileage formula synhtetic 10-30 oil. and doing reasonable oil consumption. Most common cause is valve seals and PCV SYSTEM clogging up(not just the PCV valve. Today's cat converters hide oil burning much more than days of old.....

 

I have been using Castrol Edge Full Synthetic since I bought it years ago with around 62,000 miles on it. My cat converters are no longer in it - have a tune that allows me to run w/o them now.

So it sounds like your using some oil between oil changes as well?

How easy is it for a person to have a mechanic check/service the PCV system for clogging up?

 

YUP, but only a quart in 5k miles, and for the driving conditions(up and down BIG hills) quite acceptable. As for servicing the PCV system, would entail valve cover removal(there are baffles in them that trend to "gum up" and also checking intake manifold ports for the system. Valve stem seals getting brittle and alowing oil to suck thru the valve guides is quite common for many different high mileage motors, and can be quite a job on some motors to replace.
I suggest you try their High Mileage formulation of your Castrol oil, and see if it helps.
I was under the impression that cats. were federally mandated.......

 

I am also burning oil. About 1 quart every 800-1000 miles. Yes, that much. It really bothers me. I think I've got a stuck piston ring and I think it's also the cause of my issue with the MDS solenoid. I was using Amsoil but that was getting expensive so my last oil change I switched to Castrol High Mileage. I've tried using Marvel Mystery Oil to try and loosen it up, but no luck so far. My next option is to try something I've read about on another forum called AC Delco Upper engine & fuel injector cleaner. Basically it requires the removal of the plugs so you can pour this on top of the piston and let it sit for 24-48 hours.

What is laughable is the last time I spoke to a tech at the local Dodge dealer and asked about the excessive loss, they stated that "This is normal". I'm like, "Do you add 1 quart to your vehicle every 1000 miles? Didn't think so."

 

I check mine every 1k or so, and typically go through about 1qt every 5k or so. I use Amsoil, not that it matters....but I don't think I have any issues with having to put in .5qt half way between intervals.

 

Well, if you try the AC Delco Upper Engine & Fuel Injector cleaner and it works (and how you applied it) - let us know!

 

are you guys using 5w 20 oil ?

 

I have the 5.7 in my 07 Chrysler 300C, and I use Mobil1 5/20 syn, and a bottle of STP oil treatment in the blue bottle that states that it is safe to use with synthetic oil, and I lose no oil between oil changes. (82,000 miles on the car)
The STP oil treatment in the gold bottle that is made just for synthetic oil use, is too thin, and not much good for thickening up the oil.
I know with MDS you have to be careful about which grades of oil you use, as oil that is too thick can cause issues with MDS operation.
I have zero issues with MDS function using the STP oil treatment (Blue bottle).
Since synthetic oil is so much thinner than regular motor oil. if there is any potential for a leak, an engine will lose more oil if synthetic is being used, but the STP oil treatment looks like molasses coming out of the bottle, which then helps to thicken the oil up a bit more, while at the same time giving better cold start up protection.