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  Topic Review (Newest First)
06-28-2021 12:31 AM
Delta0
Quote:
Originally Posted by Bigrigr View Post
To clarify, I was running 10W-30 conventional oil on a 5K oil chnage interval. Now to double clarify, Walmart no longer carries the straight conventional oil. I was forced to buy the synthetic blend this last go around. Only time will tell if my oil consumption stays down....I'm not a big fan of changing brands and oil types very often....
Thanks Bigrigr.
06-27-2021 02:45 PM
Bigrigr To clarify, I was running 10W-30 conventional oil on a 5K oil chnage interval. Now to double clarify, Walmart no longer carries the straight conventional oil. I was forced to buy the synthetic blend this last go around. Only time will tell if my oil consumption stays down....I'm not a big fan of changing brands and oil types very often....
06-25-2021 06:10 PM
sdg3205
Quote:
Originally Posted by juan_carlos__007 View Post
Mine was burning oil especially on startups I saw excessive white smoke out the tailpipe. Replaced $3 pcv from autozone issue no longer present. If the pcv clogs up theres no vacuum on crankcase which is needed for oil piston rings to keep excess oil below cylinders.

White smoke? That’s not typically what you’d see from burning oil.

It’s not necessarily the vacuum that draws from the crank case, it’s the “positive crankcase” pressure that pushes the oil out the PCV valve from combustion blow-by, back into the intake manifold and then back into the cylinder to be burned which is what we see out the tailpipe.

The windage tray keeps the oil “below the cylinders” and positive crankcase pressure is more likely to push oil past gaskets and seals than rings.
06-25-2021 11:55 AM
Delta0
Quote:
Originally Posted by Double E View Post
I think the question is more around what weight and conventional or full synthetic Super Tech.
Yep
06-25-2021 11:53 AM
Delta0
Quote:
Originally Posted by Bigrigr View Post
You missed the part where I said Super tech...Its Wal-Mart's house brand.
Thanks Bigrigr
06-25-2021 11:27 AM
Double E I think the question is more around what weight and conventional or full synthetic Super Tech.
06-25-2021 08:33 AM
Bigrigr You missed the part where I said Super tech...Its Wal-Mart's house brand.
06-25-2021 01:11 AM
Delta0
Quote:
Originally Posted by Bigrigr View Post
Mine was going through about 1 quart every 1000 miles. I had rescued it from its two year slumber in the PO's front yard. I finally got a handle on it when I changed the PCV valve, and switched to super tech oil. My thinking was, that if it was going to go through that much oil, i would buy cheap oil until I could tear it down and fix it right. Miraculously, the oil consumption has gone way down. I believe its maybe one quart per 5K miles now. Not trying to sell Wal-Mart oil here, but I did alot of research before I jumped to it. I guessing that the oil must have some additives that helped to swell the valve guide seals. I have now put about 5K miles on this oil, since switching. So the changed happened fairly quickly. I would bet that there are certain additives that one could add to their oil that would help in the same manner as well, but I wouldn't recommend the stop leak garbage. Lucas, Marvel Mystery oil, etc come to mind.....
Which Wal-Mart oil did you buy please?
06-24-2021 08:55 PM
Bigrigr Mine was going through about 1 quart every 1000 miles. I had rescued it from its two year slumber in the PO's front yard. I finally got a handle on it when I changed the PCV valve, and switched to super tech oil. My thinking was, that if it was going to go through that much oil, i would buy cheap oil until I could tear it down and fix it right. Miraculously, the oil consumption has gone way down. I believe its maybe one quart per 5K miles now. Not trying to sell Wal-Mart oil here, but I did alot of research before I jumped to it. I guessing that the oil must have some additives that helped to swell the valve guide seals. I have now put about 5K miles on this oil, since switching. So the changed happened fairly quickly. I would bet that there are certain additives that one could add to their oil that would help in the same manner as well, but I wouldn't recommend the stop leak garbage. Lucas, Marvel Mystery oil, etc come to mind.....
06-24-2021 02:07 PM
juan_carlos__007 Mine was burning oil especially on startups I saw excessive white smoke out the tailpipe. Replaced $3 pcv from autozone issue no longer present. If the pcv clogs up theres no vacuum on crankcase which is needed for oil piston rings to keep excess oil below cylinders.
06-24-2021 01:56 PM
Double E Agree on the valve stem seals still being in need of replacement. That's the mileage at which point they're giving up no matter what.
I also support the pcv system possibility and will toss in that with that much loss, there is a leak dripping onto the cats and it's burning off there.
That is usually from the valve cover gaskets, both of them.

The front crank seal is another common leak point at this age and is not too tough to swap.

Rings giving up some seal is certainly possible but I've seem several 4.7L piston borescope images at that mileage and there is still a nice cross-hatch pattern on the walls. Not the that the rings are not also worn but I'd go after other areas first before settling on rings.

Also interested in what the average monthly mileage is...
06-24-2021 01:28 PM
Delta0 How many miles do you drive per month please?
06-24-2021 10:35 AM
Eng208 Check your PCV. May be building crankcase pressure and blowing oil pst the rings.
06-22-2021 03:24 PM
sdg3205
2003 Jeep Grand Cherokee 4.7 L powertec motor burning oil.

It’s both. Valve stem seals are a given at that mileage. Judging by your description it’s also the rings. Given the blow by you could use a catch can off the PCV to cut down on the smell but it won’t fix the consumption.

Only solution is a rebuild.

I’d pull the engine if you’re doing the bottom end. No question.
06-22-2021 03:22 PM
[email protected]#4
2003 Jeep Grand Cherokee 4.7 L powertec motor burning oil.

Hello, I have a 2003 Jeep Grand Cherokee 4.7 L power tech motor with 195,000 mi on it. It is burning oil to the tune of about three to four quarts of oil per month. I usually do not see any smoke coming out of the exhaust in the morning when I first start the engine
Usually after driving for 3 hours or so give or take is when I usually see the smoke coming from the exhaust it smells like burnt oil. I think that my rings need to be replaced. Since I do not see any smoke first thing in the morning after I start it, I do not think it is the valve guides or seals. What are my options as far as repairing this issue? I have rebuilt a couple of engines in the past small block Chevrolets. However, I would rather have someone else do it in this case. Is there a video that is available that specifically gives you the exact procedure for fixing this repair? should I just leave the motor in the vehicle and take the top of the motor off then drop the oil pan and change the main bearings, rod bearings? Any and all responses and suggestions are appreciated.

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