what oil to use

[Rick Anderson]

I think that people are saying ... if your motor is filled with crud, you don't want large chunks of it breaking loose and circulating thoughout the oil passages. Not because the crud holds the motor together (of course not, nuts and bolts hold the motor together), but because those loose chunks of crud can clog an oil passage and starve a bearing or some other section of the motor of oil, causing it to fail.....

That is a valid concern, and I can see people in that situation, that are trying to fix up an old vehicle that has suffered from the neglect of the previous owner, I am in the same situation at the moment (vehicle wise, at least my XJ's previous owner changed the oil regularly so the motor is not gunked up).

My point is, SYNTHETIC OIL is no more likely to instantly break off those chunks than fresh conventional oil, probably less likely than using Transmission Fluid or High Detergeant Additives in an attempt to clean the motor.

There are pros and cons to using Synthetic Oil, so I'm not some Synthetic Oil Evangalist, plenty of people use good quality conventional Oil and I'm sure thats the correct choice for them. I'm trying to dismiss this misconception that Synthetic oil is 1/3 synthetic oil, 1/3 detergeant and 1/3 powerful solvents. Its simly NOT true, Synthetic is less likely to leave behind deposits and form sludge than conventional oil, its cleaning power is about the same. So argueably, Synthetic is better for a crudded up motor than conventional, because its adding less deposits and sludge on top of the existing as it cleans away the existing sludge and crud at the roughly the same rate as normal oil.

Like you, I don't know what the right answer is to ungunking a heavily gunked motor, I supposse any course of action will always risk the gunk traveling thru the motor and creating worse damage. The course of action of doing nothing different and hoping the crud/sludge and gunk stays together is probably more likely to eventually suffer the migrating chunks damage. Your Analogy about Clots in the human vascaltory system, I believe that is the delima with clots nowadays, the doctor's damned if he does, damned if he doesn't, no matter what course of action they choose, there is always a good risk of the clot breaking free and traveling somewhere to do more damage.

Personally, if I had a motor that was all gunked up, I'd do SURGERY, pull the valve cover and oil pan and clean out as much gunk as possible physically myself and get it all out of there. Then I'd run good oil with cleaning additives and change the oil and filter often, in hopes of catching all the chunks.

My approach may work and someone that adds an oz of detergeant additive to their oil would suffer a traveling chunk of crud that destroys the motor, or next week the results would be vice-a-versa. The bottom line, I thinks its literrally a crap shoot what will happen as you try to remove the crud, but I still don't think it will get better, or even stay the same, if you just ignore and declare that any attempt to clean it will result in the dreaded migrating chunks.

 

[UltimateG]

Those that disable their system for for a cooler looking mini air filter on the valve cover ... are doing nothing but shortening the life of their motor.

Sorry for the Noob hijack; I was thinking about adding one of those little filters myself, just to clean things up under the hood. How are they less efficent and functional than a hose running across the engine to the big air filter?

Thanks

 

[BCKNBLK]

SBrad001---Love the save on that whipped boy. Its even worse when they admit it. Just break 'em down, man, just keep breaking 'em down...lol...

 

[Rick Anderson]

Sorry for the Noob hijack; I was thinking about adding one of those little filters myself, just to clean things up under the hood. How are they less efficent and functional than a hose running across the engine to the big air filter?

The breather tube, that goes from the valve cover to the air cleaner box, that just draws in fresh air. So replacing that with a mini air filter, would not be much of a change. If you replace both ports of the system with mini-air filters or plug on of the ports (which many people do), then you disable the system and create problems. Make sure to block off the hole in cover of the air filter box, otherwise you'll be sucking unfiltered air into the motor. You can argue that the air filter box will supply cooler fresh air from outside the engine compartment, but I think the effect would negligable.

The problem is people that don't understand the system, cut/re-route/remove hoses that disable or hamper the system and then suffer the consequences, which is usually gunking up the motor.
The CCV or PCV valve must be connected to the proper vacuum source, the tube in good shape (they crack) and clean/clear and the valve/orifice itself must be clean and in a good shape. The CCV orifice or PCV valve controls the flow of air thru the crankcase, and allows the motor to suck out the moisture and corrosive fumes, which would otherwise contaminate the oil and create crud and sludge. The system will suck in fresh air from the breather port, that needs to be filtered as well, to prevent dirt from being sucked into the motor.

When the system gets clogged up, usually the CCV orifice or PCV valve gets clogged first or the vacuum line cracks or clogs, then pressures don't even out in the crankcase and you get oil being blown out of every place possible out of the crankcase and blowby past the rings and cause oil burning.

 

[Rocketman]

There are thread upon threads about this so I might as well express my OPINION!

I switched to M1 on mine at 180K+ and have had only a few minor issues which probably aren't related anyway. I'm a technology geek. Synthetics are BETTER PERIOD. Almost ALL NEW vehicles come off the line with synthetic, the military uses synthetic, major fleets use synthetic. Pick a flavor, be consistant, use quality filters.

Royal Purple by the way makes GREAT STUFF. I use the MAX ATF in my AW4 (YES, it is a DEXIII equiv) It runs so smooth and so much cooler under load. Easily 10-15 degrees cooler. For all you out there with an AW4 wanted to ensure and extend it's life. Get a 5 gallon bucket of Max ATF (you need 16 quarts) and find a shop with a BG Transmission machine and use it to flush and clean your tranny. (a new filter at this time is nice too) It's like getting a new trans literally

 

[bacelaw]

heres a question: anyone ever use that engine oil additive that they have on display at autozone? you know, there are two gears, one with regular oil - one with the additive, you spin the gears and the additive coats them way better, and for longer?

anyone have a clue as to what product im talking about?

 

[Rocketman]

That's the Lucas additive. I've never felt the need or been brave enough to use it.
If you are concerned about the "inside condition" of your engine, pull the valve cover. It'll give you a good indication of overall condition. If it and the CCV baffles are all gunked up, chances are, the rest of the CC is too. In which case, my suggestion, is find a shop with a BG machine and have them flush your CC.
I CAN NOT sing enough praises to the glory that is BG. Their auto maintenance machines are like having "Scotty" working on your warp coil!!

 

[RichP]

The machines do a good job, I do our jeeps yearly on the flush machines, makes coolant changes just so much nicer. The oil flush machine also does a good job the only thing you have to watch with it is the solvents they use in the flush mixture tend to soak into the sludge and keep working after the machine is done and the new oil and filter are on. Result is you have to watch your oil for a few weeks, after a couple of days the solvents will clean out more sludge and that can clog the filter before you do an oil change, best seat of the pants method is to check your dipstick and when you can no longer read thru it change the filter.

 

[Rick Anderson]

Lucas has an excellent rep, but I don't see the need for their oil stabilizer additive. The motor is not like those gears in their display, it pumps the oil everywhere it needs to be, that or it drips down ontop of a few things, which the stabilizer might inhibit that dripping and flow.

Now a splash type lubrication system, like in a manual transmission or axle, maybe that stabilizer would give some benifit.

BG, I've heard enough good things about them, that if I don't know which way or the other, I'll go off their good rep and buy their product over others OR buy a service from one of their machines if I need it.

 

[Jay Welch]

Homebrew....more discussion here.


http://www.naxja.org/forum/showthread.php?t=47018

 

[kevin s]

Am I the only one here using Amsoil?

 

[87manche]

I put some lucas stuff in my AX-15. It did quite down the box a little bit. Of course it's just masking my bad inoput shaft bearing. but it did slow the leak beacsue of the extra "stiffness" in the oil.
I put it in the crank case. Then I got a lifter tick at startup. this was mixed 1 quart to 5 regular.
Took it out and the lifter tick went away. must be too thisck

 

[Rick Anderson]

Yea, When I look at that display for the Lucas additive in the stores, I get this impression that all its doing is increasing the viscousity. Which in some cases is NOT a good thing. Its probably more complicated than that, but I'm sure in a lot of ways it will act like a higher viscousity oil with the Stabilizer Additive.

 

[Rick Anderson]

Homebrew....more discussion here.


http://www.naxja.org/forum/showthread.php?t=47018

Some posts in there about people using Castrol Syntec. Its NOT true Synthetic, like most people think Synthetic is. Castrol Syntec is an ultr-refined conventional oil that goes through a synethesising process called Hydro-Cracking, that creates more uniform hydro-carbon molecue chains.

PAO Synthetic oil is made from pure gases that are mixed and processed to engineer the exact molecue and base stock desired.

Castrol Syntec is superior oil, and it does have many of the properties of synthetic oil that we are familiar with, but Mobil1 PAO Synthetic Oil is considered better, and Castrol only spends half as much to make their Syntec, than others do to make PAO oil, BUT THEY CHARGE JUST AS MUCH FOR THEIR CHEAPER OIL.

 

[Jay Welch]

Yep. If I remember correctly, only 5% (max) synthetic product in the blends.

 

[RNMCGUIRE]

I personally have never believed in any oil additives. Most people that know about engines will not advise you to use them. Racing applications may be different but for regular automobiles, they are a waste of money in my opinion. I read an article in Consumer Reports a couple of years ago where they took several NY City taxi cabs and tested every major brand of oil and many of the additives like Slick 50 etc. They tore the engines apart and checked all the internal parts and measured the clearances and such. Then they reassembled them and put different oils in each. They drove them for about a year and then tore the engines apart again. They found that no brand of oil provided any better wear protection than another and that the additives proved to do absolutely nothing and were a complete waste of money. I found this to be a non-biased report and reflected "real world" results. Oil companies like to talk about all kinds of technical terms and unless you're a petroleum engineer or chemist, you won't have a clue what they're talking about. Regular changes with a quality oil and filter are your best bet.

 

[xjchris98]

My jeeps got 85k on her, Im gonna use the mobil clean 5000, but which is better to use...5W-30 or 10W-30 for summer?

 

[TGFH]

It's not a XJ - but I just put a 1992 Volvo 960 (2.9L) out to pasture with 297,874 miles on her - without ANY engine problems at all. Mobil 1 all the way. And I'll even admit to getting lazy on the changes - once or twice over 8,000 miles between. Great stuff!

 

[96 Cherokee]

Am I the only one here using Amsoil?

No you are not the only one. I just switched from Amsoil Series 2000 0W-30 to Series 3000 5W-30. Using the Amsoil dual remote bypass. Get my UOAs done by Blackstone Labs. My Jeep has 236,000 miles, approx 80% of those are rural mail route miles. Still runs like a new one. BTW, the valve cover has never been off. Went to the Series 3000 because the Series 2000 0W-30 thickened to a 40 weight in 12,500 miles. Going to give the heavy duty diesel oil a try. May change over to the Motor Guard TP bypass filter in the future. This Jeep has never had anything but Amsoil or Mobil 1 in it since the factory fill was changed out at 2000 miles. If you want to learn about oil, filters, etc., read the BITOG forum. Those guys are into oil like most here are into Jeeps.

 

[zj to xj]

so what oil companies make a true pao; valvoline qs etc. I know royal purple, amsoil, mobil probably are but what else???Hasta