5w-20 for 98 Trooper?

[Lazy JW]

Thanks to ya'll at BITOG I am on the first phase of doing an Auto-RX treatment on my 98 Trooper w/3.5 V6.

These engines apparently have a design flaw; the drain-back holes in the piston/ring assembly being too small and/or too few to allow adequate drain-back, resulting in relatively high oil consumption.

As these holes become progressively plugged with carbon, the oil cunsumption increases. My engine has followed this pattern, thus the Auto-RX.

My question is: When the Auto-RX has done its work and I proceed with "normal" oil OCI's, might a 5w-20 oil have a better ability to return through the already compromised drain-back holes, thereby giving an improvement in oil consumption? I have always run 10w-30 as recommended in the manual.

This engine will have just over 100k miles when the Auto-RX is completed.
Thanks,
Joe

 

[Mike242GT]

Sounds like a maintainence dose regimen of Auto RX might be in order. If Isuzu doesn't spec 5W-20 for that engine, I would avoid it. There could be issues in other areas than the one you mention.

 

[Brett Miller]

Your Trooper will drink 5W-20 faster than the old geezer at the bar drinks Old Grandad. I wouldn't do it.

 

[Lazy JW]

quote:

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Originally posted by Brett Miller:
Your Trooper will drink 5W-20 faster than the old geezer at the bar drinks Old Grandad. I wouldn't do it.

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Indeed it may. Having driven plenty of old junkers in my time I have had ample opportunity to observe the drinking habits of an oil burner. However, this is not a typical oil burner in my experience, this being the first one I have owned that burned oil due to a design flaw, rather than simply worn out (I think).

Typically, worn out engines burn oil due to poor ring sealing/scraping (I will ignore other areas such as valve guides, etc. for this discussion). This engine has been driven moderately since new, 3K dino OCI's. Yup, I very well could extend the OCI's, but my point being that this engine has been well cared for and never abused. It really SHOULDN'T be worn out yet.

It still starts/runs great, good power, fuel economy hasn't dropped, none of the usual symptoms that accompany a worn-out engine. I have always used heavier oil in an oil burner to slow the consumption. I do believe that using heavier oil than normally specified actually ACCELERATES the wearing process, something I do NOT wish to do with this engine.

Since becoming more oil-educated here at BITOG I have become more aware of the viability of thinner oils. If they are indeed superior at pumping up and getting INTO the nooks and crannies, it seems logical that thinner oil just may get OUT of those places quicker as well.

And the problem with these Trooper engines seems to be that the oil gets dammed up and cannot return quick enough. Hence my theory proposing thinner oil.
Joe

 

[G-MAN]

I think you'll just have to try 5w20 for at least one OCI and see how the consumption goes. And then at the end of the OCI do a UOA and see how the wear numbers look. Reduced consumption + good wear numbers = best case scenario.

 

[Ramblin Fever]

FWIW - I have the 3.2L sohc in a '97 Rodeo, which is basically the same engine as the 3.5L. I would NOT run a 5w-20 oil, personally.

There has been one guy who ran 5w-20 oil in his 2002 3.2L dohc engine and didn't have any issues, and in fact, stated that it ran real smooth. But only ran it for a few thousand miles before going back to a 5w-30.

I allowed my engine to idle with 5w-20 Motorcraft oil a few weeks ago, to see if the noise I was hearing was linked to a lifter. Let's put it this way, the engine got REALLY loud just idling - dumped some out and mixed in 15w-40 Motorcraft, quieted it down real quick.

FWIW - your engine is FAR from being worn out, I have 156k on mine, babied just the same as yours, and mine still has excellent power and doesn't use more then 1/8-1/4qt in 3k miles.

If the oil usage on the 98+years are watched very carefully *shouldn't* be an issue with going to 200k plus. The design flaw does seem to be between the 98-99yrs, and many have thrown a rod even with a full sump, but it's more common to hear of those throwing a rod due low oil level.

Aside from that the bottom end on these 3.2L sohc, 3.2L dohc, and 3.5L's are very stout.

 

[JR]

Lazy JW I completely understand your thinking. I am aware of the oil consumption problems that many people experiencee with these engines used in the trooper. But I do not have any personal experience involving this problem or these vehicles, So I can not accuratly say what to or not to do. But from what I have read, heared, and learned the oil consumption problems experienced with these engines are caused from the engineering defect of the ring packs of the pistons. It is my understanding that this defect is caused by the use of drain back holes that are appearently to small or the lack of an sufficent amount of drain back holes. This defect in design causes a lack of adequate drain back of lube oil that the ring pack straps of the cylinder walls to return to the lube oil sump. And since the lube oil is unable to leave the ring pack it is thus forced to drain the only other way it can. And thatis to the combustion chamber. And thus resulting in the relatively high lube oil consumption that you are experiencing. I can speculate that after time and operation that these drain back holes could, can, and do become affected by the normal by-products of internal combustion, which we all commonly know as carbon. So I strongly agree with you impamenting the Auto RX. It can do nothing but good. I can not say as to how much it will help, But I believe that the results will be well rewarded. As to your inquiry to the use of a thinner oil, I have to say that I completely understand and back your foundation for the use of thinner oils. It is appearent that the main cause of this oil comsumption problem is from a defect in design. But this defect in design is one with multible factors. And your inquiry addressed one, which is that the oil is to thick to adequitly drain back to the oil sump. I have too say that if this was my vehicle and engine, taking in consideration that it only has around 100K miles on it, I would after completing the Auto RX give the 5W-20 a try. Personaly I have used 5W-20 with great results in many different vehicles and engines that were spec'd for thicker oils. I would recomend to use a 5W-20. And for the guys that believe and preach that 5W-20 is to thin, this guy has said that he doesn't drive aggressive or hard. Ford Fleet P-71 Crown Vic Police Interceptors with a Modular 4.6 litre V-8 have proved to be as reliable with the use of 5W-20's, since ford started using it in the 2002 model year, as they ever were before the use of 5W-20's. f these big V-8's survive day in and day out without fail with the severe operating conditions and abuse they see every second they are used, I think a 5W-20 will prove to be more then sufficent in a small trooper that is "babied compared to the driving habits of many people." I can not say that a 5W-20 with completely stop oil comsumption in your engine, But I think if any change in your oil selection will, a 5W-20 will prove to be the most efficent.

 

[Gary Allan]

Do what GmanII suggests. If you don't encounter any obvious issues, stick it out through one OCI. Do a UOA to verify that there's no inordinate conditions because of it's use. Then be happy, be free (visions of Stallone in Demolition Man) ..be well

You will probably hear HLA noise at idle. That, in itself, isn't an issue. It should be all of them, though ..and not a pronounced hammering...just ticking. My 3.0 Mitsu had HLA noise on everything except 20-50 ..yet consumed nothing over the full spectrum of oils from 5-20 - 20w-50. The only change that I could detect (other then noise at idle) was short trip fuel economy

 

[427Z06]

quote:

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Originally posted by Gary Allan:
different lube systems and how they do it

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That guy went all out on the graphics, didn't he.

 

[Winston]

I do not think the thinner oil will make much difference whether or not the oil will drain back through the oil control rings. Once they get plugged up with carbon, the viscosity of the oil will not make a difference. ARX is your only hope.

 

[Gary Allan]

I guess he wasn't an artiste~

 

[Ramblin Fever]

I keep having to remind myself that, technically when you're running a 5w-30 it turns into a 5w-20 in a matter of a thousand miles or so, anyway. So it can't hurt to try it, specially if you live on flat-land, no towing, no mountains.

 

[Lazy JW]

quote:

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Originally posted by Winston:
I do not think the thinner oil will make much difference whether or not the oil will drain back through the oil control rings. Once they get plugged up with carbon, the viscosity of the oil will not make a difference. ARX is your only hope.

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I am hoping that the Auto-RX will un-plug the drain holes, then maybe a thinner oil will drain back more readily. I don't intend to try it until the Auto-RX is completed. Not sure what brand, maybe some of that fancy Pennz Platinum I keep reading about here. Lots of time to ponderize before the RX treatment is done. Decisions, decisions....

Thanks,
Joe

 

[427Z06]

Given the design flaw in this engine, and the fact your approaching 100K miles, you might consider a double AutoRX treatment as prescribed by the instructions on the AutoRX website.

After treatment, maintenance doses of AutoRX or LC use may be something to consider too.

I like G-Man II's procedure for trying a 5w20.

 

[Winston]

How does oil get to the piston rings? Is it from the crankshaft, to the rod bearing, up the rod, to the wrist pins, then splashes onto the cylinder walls?

 

[Gary Allan]

quote:

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Originally posted by Winston:
How does oil get to the piston rings? Is it from the crankshaft, to the rod bearing, up the rod, to the wrist pins, then splashes onto the cylinder walls?

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different lube systems and how they do it.

 

[Winston]

I think ARX X2. With a ARX maintenance dose would be the Rx for your engine.

 

[427Z06]

quote:

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Originally posted by Gary Allan:
I guess he wasn't an artiste~

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Well...you know kids these days...if it isn't 3-D with the parts moving...you have to give them another dose of riddlin'.

 

[pinoy99]

From personal experience(2x doze) AutoRx will not have any effect. Only thing that could possibly work is a piston soak.

40 weight oil & 3k OCI would keep the consumption to minimum.

 

[trooper99]

Double that on the no effect. I ran two cycles of AutoRX at 90K on my 99 trooper, no help. Currently burning about a qt/700 miles. Im now trying Rotella 15W-40 which somebody reported success on their trooper. I've also done LC shock and maint doses without success. Piston soak is the only thing I haven't tried yet.