Did an oil change to the 4.7 yesterday since its new to me. Motor showed signs of random oil pressure drops down to the lower "good" mark on the gauge, seemingly when the oil got up to temp, this showed on a 10 mile loop I was doing to gain a warm & fuzzy feeling for the motor. Had approx 1 quart of MMO (Marvel Mystery Oil) in there to start to clean it up. Note the motor's behavior did not change after the MMO install. I did the 10 mile loop approx 10 times to allow it to do its thing, if anything.

Oil came out black with a few small chunks of debris in the pan. Previous oil change was in April 2021, no idea how many miles on the oil, oil did not look particularly black on the dipstick and appeared pretty thin in the pan.

New oil is a Castrol (?) 10w-30 high mileage oil. Looked for the recommended Penzoil but everything they have now claims to be made from natural gas so I went with what I thought would be the next best bet. The new oil did not indicate synthetic blend of any kind (which is why I picked it). Also picked up a bottle of Hot Shots Stiction Eliminator and dropped in the recommended amount, 24 oz @ 4 oz/qt. Fired it up and as expected with the thicker oil and a cold motor, pressure was solid and fairly high, right up there below the upper "good" tick mark on the gauge. After checking for leaks and finding none, off I go on the 10 mile loop. Engine behavior changed slightly where it would hold pressure better thru the 10 mile loop. Not expecting anything to change immediately because of the SE, stopped back off at home for a bit then headed back out for a longer drive, 35~45 miles (est). Oil pressure held for approx 20ish miles then did the same thing it did before, dropped to the lower "good" mark on the gauge. Note: Previously it would drop far sooner then it did. Got off the hiway and pulled over for a bit thinking and began to wonder if the oil temp might be contributing to the drop. Hummm... Ok so I cranked up the heater on high to see if it would repeat at all on the drive home (was at turn around point) and it did not.

Now with no more time to work on it in the near future, it will sit as is and get used as needed. Will take it for longer spins to evaluate when possible and to let the SE do its thing.



https://www.hotshotsecret.com/stiction-eliminator/

So some background on the use of SE... My Ram has 465k on it now, around 360~380k its oil usage began to randomly increase. It got to a point where it was up to 3~4 quarts of oil over a 7k mile period on a 10k OCI. Truck has been on Royal Purple 15w-40 since about 100k, it also has a bypass filter kit from Amsoil which is supposed to filter down to the 2 micron range. Seeing the 3~4 qt loss was an indicator to me that the motor was nearing the end of its life (EOL) and a rebuild was in the near future. Having nothing to loose, I gave the SE a shot to see the cause and effect. 1st oil change with it installed (1 qt with a 13 qt capacity), over 10k miles oil use dropped to approx 3 qts (IIRC). 2nd oil change oil loss dropped to ~1.5 qts over that 10k OCI. Engine performance improved noticeably. My conclusion there was some of the piston rings were stuck and it was allowing increased blowby. Now that they were free, compression settled at what it would be with no rings "stuck" which would account for the change in performance.

There it remained up until around the 450k mark. Oil loss started to increase gradually and again, thought my motor was nearing EOL for real this time. At approx 2k into the current OCI I was down 3 quarts, topped it off and 1k miles later, down another 2 quarts. Happened to be youtube surfing for something unrelated and came across a video where the presenter was giving an over view of a turbo they were selling or rebuilding or something to that effect. Stopped to watch it and something he said turned on the overhead light with an ah ha moment. Bright enough to put on sun glasses... The comment he said was that if there is too much pressure in the block, aka not venting correctly, the oil return line from the turbo will "back up" so to speak and drain slowly. Makes sense... At that moment it occurred to me that I had not touched my breather box that sits on the valve cover in over 200k miles. It is just a brillo pad type of screen in there and what could possibly need to be done with it????

Well I was wrong... I pulled it out, shot some brake cleaner in there and a bunch of gunk came out. Knowing the brake cleaner is not going to do a good job of hitting the mesh I filled it up with ATF and let it sit overnight. 12~14 hrs IIRC. Dumped the ATF out into a container the next day and oh man was it dirty. The ATF did a great job of loosening and removing a lot of gunk left behind by the brake clean. At this point in the OCI it was around the 5k mark so I had a ways to go till the next oil change. Topped it off and rolled with it. Did not have to add any more oil for the rest of the OCI. Next oil change is at 460k.

At the 460k oil change, again, added the 1 qt of the SE (every oil change gets a qt), checked where the oil was on the dip stick to monitor it and motored on. Now at 465k, the dip stick level has not changed at all. Right where it was at the start of the OCI.

Back to the 4.7L engine...
Having this first hand experience with it, I have no problems using it and am sure it will clean the internals of the 4.7. If the funky oil pressure issue is sludge related, this stuff will clear it out. Will most likely do a 500~1000 mile OCI with whats in there depending on how the oil "looks" on the dips stick. If it turns black, I will rinse and repeat until the OCI is up there at the 3k mark.

Anyways... there it is... and semi related, the motor is going to get a 180* stat, unless I can find a comparable 190* stat before I do the swap later this month. It currently runs at 200~206* and I am not comfortable with it (iron block, aluminum heads). Would have rather found a Dak with the 360 but those are really tough to get if one even pops up, the last 2 I saw were gone in a day.

 

Dak has maybe 100 miles on it now since the install, not seeing any drop in pressure now on the gauge. It still goes down to the lower tic mark of the "good" range when down around 900~1000 rpms. Climbs with rpms and holds.

 

If you want to accurately check the pressure, you can remove the oil pressure sender and hook up a gauge. So you know where you stand....

https://dodgeforum.com/forum/2nd-gen-dakota-tech/389123-oil-pressure-drop.html

 

170 miles into SE use, oil pressure fluctuations reduced significantly... the little woman had the truck over the weekend while i did work to her jeep jk. she reported nothing unusual with it i took it for a 35ish mile drive out on the hiway and saw nothing out of the ordinary on the gauge. no more drops while in a steady state rpm...

173700 @ install

 

When using Marvel to clean the engine, an easy 50 mile drive is better than 10 miles. And, it does thin the oil, part of how it cleans the engine, which is why you don't want to drive hard during the 50 miles, and don't want to drive more than that. Gloopy crap in the oil is sludge that the Marvel is breaking loose. My family has always used Marvel on a regular basis, as well as Quaker State oil, and even after a couple hundred thousand miles the engines are clean inside. I had to change valve cover gaskets on my mother's truck, 250K miles without ever being cracked open, and there was an eighth of an inch of varnish buildup inside the valve covers, only in the top two corners, covering about 3 square inches centered on the corner. Other than that, everything was as clean as an engine with 10K miles on it.

Those breather filters are usually pretty cheap to just replace, should be replaced at least once a year. It's been years since I had to buy one, but when I did I think it was just a couple of bucks.

If you REALLY want to clean things out, go down to a Chevy dealer and pick up a can of Top Engine Cleaner, and use it as the directions say, if it's still sold. That stuff will burn off everything accumulated in the intake and the piston chambers, and if it's really dirty inside so much smoke will come out of the pipes that you'll swear the engine blew.

 

Yeah the MMO install... it was in there for more than just the 10 mile loop... did that loop approx 8~10 days and never really saw any big change. It might have helped some, the oil I dumped came out pretty dark yet it was still decent on the dip stick. The SE on the same route, on the 2nd 10 mile loop, there was a difference in the way the OP gauge was reading... (IIRC, got a lot going on lol). It gave me a warm fuzzy feeling to expand the loop further and put more miles on it. Confidence in it is building to the point where I'll take it farther out now. I believe it has a bad left front wheel bearing, it sounds noisy to me. It could be the tire but I dont see it being worn funny or different than the other 4... They are nearing their end of life and will have to swap them at some point.

On the breather filter... are you talking about the ones on each valve cover near the firewall? I read those got revised into just a large port on later engines. Thinking I am going to revise the PVC setup and ditch that one that is on the oil filler tube. If those valve cover breathers are revised then I may go to an in-line PVC valve and tap off those into the intake manifold. Found one at Napa, CRB 29251 that will need investigating https://www.napaonline.com/en/p/CRB29251 Thinking 1 off each valve cover to a vacuum source should do it.

Your Top Engine Cleaner suggestion... that is similar to the sea foam fog thru the intake right? The sea foam is on the list of things to do and will prob get to it this week. Last week I had been taping up cracked hoses with electrical tape in an effort to stop the leaks for now until I can get the hoses swapped. (addressing the CE light). Turns out the last fix turned the light off... there was an open hose going (I think) to the leak detection pump (?) over by the left front headlight, plugged it initially until last week where I re-attached it to the plugged port on the intake manifold. That was right before the handoff to the little woman, last night... no CE light on last nights drive so looks like I fixed that one as well.

knocking off problems at a decent pace

Once I get it road worthy for long trips, out comes the transfer case out of the ram for its 2nd rebuild. Has a vib off throttle in gear. This would be the 2nd time those symptoms presented itself. 1st time the rebuild fixed it as well.

 

I did the upgrade to the newer style of PCV Valve to reduce or eliminate sludge.
When i bought my Dakota 4.7l it has a little sludge in the oilfiller neck.
I removed my valve covers and cleaned them out, there was some black sludge, but not much.
I changed oil this weekend and to be curious i removed a valve cover to check and everything is as clean as a new engine, so i'm thinking this worked for me.
So i made the change to the newer type of PVC valve and had no sludge ever since.
Here is a link to Martin Built Video, he explaines it very well.

 

Thanks... I have watched that video which had me thinking about the changes that went into effect over the years on that motor. That is where I thought it might be good to go to a newer configuration. Then... I saw what was done on the 3.8L wrangler motor the little woman has... seems to be a larger draw on the vacuum from the intake manifold, and it comes from just the one valve cover like other motors. This makes me wonder what is up with the 2 breathers being on each valve cover... It also makes me wonder why the opened up the breather from a fixed orifice to just a feed thru port.



On a separate note... getting excited for tuning this motor (and then the Jeep motor assuming I dont blow this one up hahaha) My goal would be all about bottom end torque, 1000-2000 rpms. Torque is king for me, solid reliable performance is the goal, always.

 

I suppose more is better ? With this set-up you have made 2 points of suction to eliminate gasses and moisture built up regulated by one PVC Valve, as i see it.
The PCV valve's are actually on the back on top of the cilinder heads, originally the left and right banks and the filler neck where only fitted on the back off the intake manifold.
The tube on the right side was going to the old pcv valve on the oil filler neck, wich was the highest point of the motor.
This was intended to eliminate the moisture to built up, but many had the problem of sludge being built op in the filler neck.
Mine has as wel when i bought it, but only a little.
So for me the solution was the way Martin explained, got one new style PCV valve on the left bank and this one is going straight to the back on the intake manifold and on the right bank straight to the intake side of the air cleaner and i plugged the hole in the filler neck.

 

That stuff in the filler neck is not really textbook sludge.

Ask yourself what is sludge? Sludge is contaminated, dirty engine oil, usually from neglect. Essentially, it is oil mixed with worn metal, oxidation and dirt. Sludge would not travel UP to the filler neck. What you're seeing here is oil vapor mixed with condensation, which is why the stuff looks like a clean yellow in this bad case photo. Condensation forms because the filler cone is so high up off the engine that it stays cooler. I never see any of this in the summer, yet in the winter a small bit will form under the cap, especially if there is a long cold stretch. Pull the oil fill cap off after even a long drive in cold weather and you'll see many droplets of water forming under the cap.

Same thing happens inside the motor every time you start a cold engine. The difference is that the engine quickly gets hot enough to burn off the condensation and nothing forms. That is, unless you mess around and put lower temp thermostats in. You might think you're reducing risk of head gasket failure by running colder, but you're actually increasing water retention and inviting this mixture into your engine, especially in the winter. Run quality thinner synthetic oil and keep engine temp as designed to quickly burn off water, also don't sit and "warm" the vehicle... it's better to drive it for quicker temp raise...also cold start pushes more gas into cylinders washing off the oil with a solvent (gas).

The 4.7L has smaller oil galleys and passages, than the 5.9, which is why folks say it sludges easier, but this issue is easily combatted.